Aqueous heat treatment liquid composition, method for manufacturing metal materials, and apparatus for manufacturing metal materials

Abstract

The present invention provides an aqueous heat treatment solution composition that exhibits good luster in metal materials after heat treatment and can suppress the cooling rate. [Solution] An aqueous heat treatment liquid composition according to one aspect of the present disclosure contains water (A), condensed phosphate (B), and glycols (C).

Description

[Technical Field]

[0001] This disclosure relates to an aqueous heat treatment liquid composition, a method for producing a metal material using the aqueous heat treatment liquid composition, and an apparatus for producing a metal material. [Background technology]

[0002] Coolants used for quenching metal materials include, for example, (i) gas or salt solution, (ii) oil-based or water-based (water-soluble) quenching fluid, (iii) water, and (iv) salt water. Cooling properties vary depending on the type of coolant, with a tendency for the cooling properties to increase in the order of (i), (ii), (iii), and (iv). Using a coolant with high cooling properties can produce harder metal materials, but on the other hand, it increases the risk of distortion and quench cracking. For this reason, the type of coolant is selected according to the desired hardness and allowable amount of distortion in the metal material after quenching.

[0003] Among these coolants, water-based quenching fluids are widely used because they have many advantages over oil-based quenching fluids, such as: higher cooling performance; the ability to adjust cooling performance by dilution concentration; less risk of fire because they do not burn like oil; reduced oil usage because they can be diluted; and a reduced risk of distortion and cracking compared to water.

[0004] For example, Patent Document 1 discloses an aqueous coolant comprising one or more inorganic salts selected from carbonates, bicarbonates, sesquicarbonates, phosphates, borates, molybdates, and tungstates, and a metal corrosion inhibitor. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2014-125680 [Overview of the project] [Problems that the invention aims to solve]

[0006] The hardening process can reduce the surface gloss of metal materials, resulting in appearance defects. In such cases, post-hardening processes, such as polishing, are performed to improve the appearance defects.

[0007] When using an inert gas as a coolant, the luster after quenching is improved, allowing for the reduction of post-processing steps such as polishing. Furthermore, in the case of oil-based quenching solutions, the luster after quenching can be improved by adding alkenyl succinic acid. On the other hand, while water-based quenching solutions generally tend to exhibit reduced luster, no studies on luster have been conducted to date. Therefore, there is room for improvement regarding the luster when using water-based quenching solutions as a coolant. Additionally, since a fast cooling rate increases the risk of distortion and quench cracking, there is also room for improvement regarding the cooling rate of water-based quenching solutions.

[0008] One aspect of this disclosure aims to provide an aqueous heat treatment solution composition that exhibits good luster in a metal material after heat treatment and can suppress the cooling rate. [Means for solving the problem]

[0009] As a result of diligent research to solve the above problems, the inventors have discovered for the first time that by blending condensed phosphates and glycols into an aqueous heat treatment solution composition, it is possible to realize an aqueous heat treatment solution composition that exhibits good luster of metal materials after heat treatment and suppresses the cooling rate, thus completing the present invention. That is, in order to solve the above problems, an aqueous heat treatment solution composition according to one aspect of the present disclosure contains water (A), condensed phosphate (B), and glycols (C). [Effects of the Invention]

[0010] According to one aspect of this disclosure, it is possible to provide an aqueous heat treatment solution composition that exhibits good luster in a metal material after heat treatment and can suppress the cooling rate. [Brief explanation of the drawing]

[0011] [Figure 1] It is a diagram showing the results of the examples, and is a diagram showing the appearance of test pieces that have been quenched using each of the aqueous heat treatment liquid compositions (diluted liquids) of Examples 1 to 3 and Comparative Example 1. [Figure 2] It is a diagram showing the results of the examples, and is a diagram showing the appearance of test pieces that have been quenched using each of the aqueous heat treatment liquid compositions (diluted liquids) of Reference Examples 1 to 7 and Comparative Examples 14 to 23. MODE FOR CARRYING OUT THE INVENTION

[0012] Hereinafter, one aspect of the present invention will be described in detail. Unless otherwise specified in the present specification, "A to B" representing a numerical range means "not less than A and not more than B".

[0013] [1. Aqueous Heat Treatment Liquid Composition] The aqueous heat treatment liquid composition according to one aspect of the present disclosure contains water (A), a condensed phosphate (B), and glycols (C). According to the above configuration, the following effects are obtained.

[0014] (1) Improvement of brightness on surface of metal material after heat treatment By using the aqueous heat treatment liquid composition according to one aspect of the present disclosure as a quenching liquid or a tempering liquid, a decrease in brightness of the surface of a metal material caused by heat treatment can be reduced, and therefore the occurrence of appearance defects in the metal material after heat treatment can be reduced. By using the aqueous heat treatment liquid composition according to one aspect of the present disclosure as a quenching liquid or a tempering liquid, the brightness of the surface of the metal material after heat treatment is improved, so that treatments such as polishing for improving poor appearance can be omitted in the post-process after heat treatment. In the present specification, the term "heat treatment" means a treatment of cooling a heated metal material using a coolant, and examples of such heat treatment include quenching and tempering.

[0015] (2) Suppression of cooling rate Regarding quenching of metal materials, when a heated metal material is put into an aqueous quenching liquid, the cooling rate is not constant, and cooling generally proceeds through the following three stages. First stage (vapor film stage): The stage where the metal material is covered with vapor of the aqueous quenching liquid and cooled through the vapor film. Second stage (boiling stage): The stage where the vapor film breaks, and foamy heat treatment oil comes into contact with the metal surface. Third stage (convection stage): The stage where the temperature of the metal material becomes equal to or lower than the boiling point of the aqueous quenching liquid, and cooling proceeds via convection of the aqueous quenching liquid.

[0016] In the case of conventional aqueous quenching liquids, since the boiling point of water is 100°C, the metal material is rapidly cooled to around 100°C after the vapor film breaks. That is, when a conventional aqueous quenching liquid is used, the cooling rate is high in the temperature range where martensite is generated in the second stage (boiling stage), so a local temperature difference occurs in the metal material, which easily causes strain and quenching cracks in the metal material.

[0017] In contrast, the aqueous heat treatment liquid composition according to one aspect of the present disclosure has a suppressed cooling rate during heat treatment, so cooling can be moderated by using the aqueous heat treatment liquid composition according to one aspect of the present disclosure as a quenching liquid or a tempering liquid. For example, cooling can be moderated by suppressing the 350-150°C cooling rate, which is one of the indicators of the cooling performance of aqueous quenching liquids. Here, in the present specification, the "350-150°C cooling rate" means the cooling rate (°C / s) calculated from the cooling time in the temperature range from 350°C to 150°C, measured in accordance with the cooling performance test method for water-soluble quenching liquids (Method B: center temperature measurement method) specified in JIS K2242:2012.

[0018] According to the aqueous heat treatment liquid composition according to one aspect of the present disclosure, the cooling rate during heat treatment can be suppressed and cooling can be moderated, so the risk of strain and quenching cracks occurring in metal materials due to heat treatment can be reduced.

[0019] The components contained in the aqueous heat treatment liquid composition according to one aspect of this disclosure are described below.

[0020] <Water (A)> A water-based heat treatment fluid composition according to one aspect of this disclosure is a water-based heat treatment composition containing water (A) (hereinafter sometimes referred to as "component (A)"), and therefore has the following advantages compared to oil-based quenching fluids: high cooling performance; cooling performance can be adjusted by dilution concentration; high safety due to the low risk of fire as it does not burn like oil; and the amount of oil used can be reduced because it can be used after dilution.

[0021] In an aqueous heat treatment fluid composition according to one aspect of this disclosure, the type of component (A) is not particularly limited. For example, distilled water, deionized water, tap water, industrial water, etc., can be used as component (A).

[0022] <Condensed phosphate (B)> The aqueous heat treatment solution composition according to one aspect of this disclosure contains a condensed phosphate (B) (which may be referred to as "component (B)" below), thereby improving the luster of the metal material surface after heat treatment.

[0023] In an aqueous heat treatment liquid composition according to one aspect of the present disclosure, component (B) can be a condensed phosphate with a degree of polymerization of 2 to 200. From the viewpoint of solubility in water, component (B) is preferably a condensed phosphate with a degree of polymerization of 2 to 10, more preferably a polyphosphate or metaphosphate with a degree of polymerization of 2 to 10, even more preferably a pyrophosphate (degree of polymerization 2), tripolyphosphate (degree of polymerization 3), trimetaphosphate (degree of polymerization 3), tetrapolyphosphate (degree of polymerization 4), or hexametaphosphate (degree of polymerization 6), and most preferably a pyrophosphate.

[0024] Examples of salts include alkali metal salts and ammonium salts. Examples of alkali metal salts include lithium salts, sodium salts, and potassium salts, with sodium salts or potassium salts being preferred.

[0025] Specific examples of condensed phosphates include, for example, sodium pyrophosphate, potassium pyrophosphate, sodium tripolyphosphate, potassium tripolyphosphate, sodium tetrapolyphosphate, potassium tetrapolyphosphate, sodium trimetaphosphate, potassium trimetaphosphate, sodium hexametaphosphate, potassium hexametaphosphate, ammonium pyrophosphate, ammonium tripolyphosphate, ammonium tetrapolyphosphate, ammonium trimetaphosphate, and ammonium hexametaphosphate.

[0026] Of these, the condensed phosphate (B) is preferably at least one of sodium pyrophosphate and potassium pyrophosphate. Component (B) may be used alone or in combination of two or more.

[0027] <Glycols (C)> An aqueous heat treatment liquid composition according to one aspect of this disclosure contains glycols (C) (hereinafter sometimes referred to as "component (C)") which can suppress the cooling rate between 350 and 150°C and mitigate the cooling process.

[0028] Furthermore, as will be described later, an aqueous heat treatment liquid composition according to one aspect of this disclosure may optionally contain polyalkylene glycols (D) (hereinafter sometimes referred to as "component (D)") which include repeating units derived from ethylene oxide and repeating units derived from alkylene oxides other than ethylene oxide. When an aqueous heat treatment liquid composition according to one aspect of this disclosure contains component (D), component (C) can suppress layer separation of the composition and improve the storage stability of the composition.

[0029] In an aqueous heat treatment liquid composition according to one aspect of this disclosure, component (C) is preferably a glycol having water solubility, for example, a number average molecular weight of 1,000 or less, and more preferably a glycol having water solubility at room temperature (25°C) (for example, a glycol with a number average molecular weight of 600 or less). In this specification, the number average molecular weight of glycols is calculated based on the hydroxyl value (mgKOH / g). The hydroxyl value (mgKOH / g) is measured in accordance with JIS K 0070.

[0030] Examples of glycols with a number-average molecular weight of 1,000 or less include polypropylene glycols such as propylene glycol, dipropylene glycol, tripropylene glycol, and their derivatives; polyethylene glycols such as ethylene glycol, diethylene glycol, triethylene glycol, and their derivatives; glycol ethers such as ethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether, 3-methoxybutanol, 1,3-butylene glycol, n-propyl alcohol, propylene glycol n-propyl ether, dipropylene glycol methyl ether, diethylene glycol monoethyl ether, tripropylene glycol methyl ether, methyl glycol, methyl diglycol, methyl triglycol, methyl polyglycol, isopropyl glycol, isopropyl diglycol, butyl glycol, butyl diglycol, butyl triglycol, isobutyl glycol, isobutyl diglycol, benzyl diglycol, methyl propylene triglycol, dimethyl glycol, dimethyl diglycol, dimethyl triglycol, methyl ethyl diglycol, diethyl diglycol, and their derivatives; and polyglycerins.

[0031] Furthermore, glycols with a number average molecular weight of 1,000 or less may be diol-type or triol-type glycols. The preferred degree of polymerization for glycols that can be preferably used as component (C) is the degree of polymerization at which the number average molecular weight is 1,000 or less.

[0032] From the viewpoint of the solubility of component (C) itself in water and the solubility of component (B), component (C) is preferably at least one selected from the group consisting of polypropylene glycol, propylene glycol, polyethylene glycol, ethylene glycol, and derivatives thereof, and more preferably propylene glycol. Component (C) may be used alone or in combination of two or more.

[0033] In this specification, the term "glycols" encompasses glycols with hydrogen atoms at both ends and glycol derivatives with at least one other group besides hydrogen.

[0034] Examples of the aforementioned "groups other than hydrogen" from the viewpoint of solubility in water include alkyl groups having 1 to 5 carbon atoms, acyl groups having 1 to 6 carbon atoms, saturated alicyclic hydrocarbon groups having 5 to 12 carbon atoms, unsaturated alicyclic hydrocarbon groups having 5 to 12 carbon atoms, and aromatic hydrocarbon groups having 5 to 12 carbon atoms.

[0035] Examples of the aforementioned "alkyl group having 1 to 5 carbon atoms" include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, and tert-butyl group.

[0036] Examples of the aforementioned "acyl group having 1 to 6 carbon atoms" include a group having an alkyl group having 1 to 5 carbon atoms and a carbonyl group.

[0037] Examples of the aforementioned "saturated alicyclic hydrocarbon group having 5 to 12 carbon atoms" include cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclononyl group, and cyclodecyl group.

[0038] Examples of the aforementioned "unsaturated alicyclic hydrocarbon group having 5 to 12 carbon atoms" include the cyclopentenyl group and the cyclohexenyl group.

[0039] Examples of the aforementioned "aromatic hydrocarbon group having 5 to 12 carbon atoms" include aryl groups such as phenyl groups and naphthyl groups.

[0040] The saturated alicyclic hydrocarbon groups having 5 to 12 carbon atoms, the unsaturated alicyclic hydrocarbon groups having 5 to 12 carbon atoms, and the aromatic hydrocarbon groups having 5 to 12 carbon atoms may have substituents. Examples of such substituents include alkyl groups having 1 to 6 carbon atoms, alkoxy groups having 1 to 6 carbon atoms, and aryl groups having 6 to 14 carbon atoms.

[0041] <Polyalkylene glycols (D) containing repeating units derived from ethylene oxide and repeating units derived from alkylene oxides other than ethylene oxide> The aqueous heat treatment fluid composition according to one aspect of this disclosure may not contain component (D), but it is preferable that it further contains component (D). By including component (D) in the aqueous heat treatment fluid composition according to one aspect of this disclosure, the cooling rate between 350 and 150°C can be further suppressed, and the cooling can be further mitigated. Furthermore, the cooling performance can be adjusted by the content of component (D) in the aqueous heat treatment fluid composition according to one aspect of this disclosure.

[0042] In an aqueous heat treatment liquid composition according to one aspect of this disclosure, component (D) has a larger molecular weight than component (C). For example, if the aqueous heat treatment liquid composition according to one aspect of this disclosure contains two types of polyalkylene glycols containing EO units and AO units other than EO with different molecular weights, the one with the larger molecular weight is designated as component (D), and the one with the smaller molecular weight is designated as component (C). Also, for example, if the aqueous heat treatment liquid composition according to one aspect of this disclosure contains three or more types of polyalkylene glycols containing EO units and AO units other than EO with different molecular weights, the PAG with the largest molecular weight corresponds to component (D), and the PAG with the smallest molecular weight corresponds to component (C). A PAG with an intermediate molecular weight may correspond to component (D) or to component (C).

[0043] Component (D) in an aqueous heat treatment liquid composition according to one aspect of the present disclosure includes, for example, linear polyalkylene glycols containing repeating units derived from ethylene oxide and repeating units derived from alkylene oxides other than ethylene oxide; and branched polyhydric alcohol adducts of ethylene oxide and alkylene oxides other than ethylene oxide.

[0044] (Linear polyalkylene glycols containing repeating units derived from ethylene oxide (EO units) and repeating units derived from alkylene oxides other than ethylene oxide (AO units other than EO units)) Examples of linear polyalkylene glycols containing EO units and AO units other than EO include compounds represented by the following general formula (I). R 1 O-(R A O) n -R 2 ... (I) In equation (I) above, R A R represents an alkylene group with 2 to 6 carbon atoms. 1 and R 2 Each of these independently represents a hydrogen atom, a C1-C5 alkyl group, a C1-C6 acyl group, an optionally substituted C5-C12 saturated alicyclic hydrocarbon group, an optionally substituted C5-C12 unsaturated alicyclic hydrocarbon group, or an optionally substituted C5-C12 aromatic hydrocarbon group. n is an integer of 2 or more such that the mass-average molecular weight (Mw) of the compound is within the numerical range described later (for example, 8,000 or more). The preferred numerical range for the mass-average molecular weight of the compound will be described later.

[0045] Examples of the "alkylene group having 2 to 6 carbon atoms" in formula (I) above include ethylene group, propylene group, ethylmethylene group, 1,1-dimethylethylene group, 1,2-dimethylethylene group, n-butylethylene group, isobutylethylene group, 1-ethyl-2-methylethylene group, 1-ethyl-1-methylethylene group, trimethylene group, tetramethylene group, pentamethylene group, and the like.

[0046] R in the aforementioned formula (I) 1 and R 2 Examples of the "alkyl group having 1 to 5 carbon atoms" represented by include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, and a tert-butyl group.

[0047] R in the aforementioned formula (I) 1 and R 2 Examples of the "acyl group having 1 to 6 carbon atoms" represented by include a group having an alkyl group having 1 to 5 carbon atoms and a carbonyl group.

[0048] R in the aforementioned formula (I) 1 and R 2 Examples of the "saturated alicyclic hydrocarbon group having 5 to 12 carbon atoms" represented by include a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclononyl group, and a cyclodecyl group.

[0049] R in the aforementioned formula (I) 1 and R 2 Examples of the "unsaturated alicyclic hydrocarbon group having 5 to 12 carbon atoms" represented by include a cyclopentenyl group and a cyclohexenyl group.

[0050] R in the aforementioned formula (I) 1 and R 2 Examples of the "aromatic hydrocarbon group having 5 to 12 carbon atoms" represented by include aryl groups such as a phenyl group and a naphthyl group.

[0051] The aforementioned saturated alicyclic hydrocarbon group having 5 to 12 carbon atoms, unsaturated alicyclic hydrocarbon group having 5 to 12 carbon atoms, and aromatic hydrocarbon group having 5 to 12 carbon atoms may have a substituent. Examples of such a substituent include an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, and an aryl group having 6 to 14 carbon atoms.

[0052] Straight-chain polyalkylene glycols containing EO units and AO units other than EO are defined as (R) in formula (I) above. A The O) unit includes ethylene oxide and alkylene oxides other than ethylene oxide. The alkylene oxide other than ethylene oxide is not particularly limited and can be arbitrarily selected from alkylene oxides having 3 to 6 carbon atoms, for example, propylene oxide and butylene oxide. The AO unit other than EO may be one type or a combination of two or more types. For example, the AO unit other than EO may be a propylene oxide unit, a butylene oxide unit, or a combination of a propylene oxide unit and a butylene oxide unit. Furthermore, the mixture may further contain alkylene oxide units other than propylene oxide units and butylene oxide units.

[0053] (R in equation (I) above) A The bonding mode of the 0) units is not particularly limited and includes, for example, random bonding (random copolymer), block bonding (block copolymer), graft bonding (graft copolymer), and alternating bonding (alternating copolymer). The block copolymer may be a reverse pluronic block copolymer or a reverse stetronic block copolymer. The bonding mode in linear polyalkylene glycols containing EO units and AO units other than EO may be any of these bonding modes, but from the viewpoint of the manufacturing cost of the copolymer, a random bonding mode is preferred.

[0054] Linear polyalkylene glycols containing EO units and AO units other than EO are preferably water-soluble. In this specification, among the compounds of general formula (I) above, R 1 and R 2 When both are hydrogen, it is called a polyalkylene glycol, 1 and R 2A polyalkylene glycol derivative is defined as one in which at least one of the groups is a group other than hydrogen. Therefore, in this specification, the term "polyalkylene glycols" encompasses both polyalkylene glycols and polyalkylene glycol derivatives.

[0055] In linear polyalkylene glycols containing EO units and non-EO AO units, the ratio (Q / P) of the number of moles of EO units added (Q) to the number of moles of non-EO AO units added (P) is preferably 1 or more, more preferably 1.5 or more, and even more preferably 2 or more, from the viewpoint of improving solubility in water. Furthermore, from the viewpoint of the cloud point, the ratio (Q / P) is preferably 19 or less, more preferably 9 or less, and even more preferably 6 or less. The upper and lower limits of these numerical ranges may be combined in any way; for example, the ratio (Q / P) is preferably 1 to 19, more preferably 1.5 to 9, and even more preferably 2 to 6.

[0056] The mass-average molecular weight (Mw) of linear polyalkylene glycols containing EO units and AO units other than EO is preferably 8,000 or more, more preferably 10,000 or more, and even more preferably 12,000 or more, from the viewpoint of sufficiently obtaining the effect of suppressing the cooling rate at 350-150°C. Furthermore, the mass-average molecular weight of linear polyalkylene glycols containing EO units and AO units other than EO is preferably 50,000 or less, more preferably 40,000 or less, more preferably 30,000 or less, even more preferably 28,000 or less, and even more preferably 25,000 or less, from the viewpoint of viscosity. The upper and lower limits of these numerical ranges may be combined in any way. For example, the mass-average molecular weight of linear polyalkylene glycols containing EO units and AO units other than EO is preferably 8,000 to 50,000, more preferably 8,000 to 40,000, more preferably 8,000 to 30,000, even more preferably 10,000 to 28,000, and even more preferably 12,000 to 25,000.

[0057] The ratio (Mw / Mn) of the mass-average molecular weight (Mw) to the number-average molecular weight (Mn) of linear polyalkylene glycols containing EO units and AO units other than EO is preferably 1.5 to 10, more preferably 2.8 to 9, and even more preferably 2.5 to 5. In this specification, the mass-average molecular weight and number-average molecular weight of polyalkylene glycols are measured by gel permeation chromatography (GPC) under the following measurement conditions and represent the values ​​converted to standard polystyrene. <Measurement Conditions> Column: TSKgel GMPWXL x 2, manufactured by Tosoh Corporation Guard column: Shodex LF-G Flow rate: 1.0mL / min Mobile phase: 0.2M NaNO3aq. Sample injection volume: 100 μL Column oven temperature: 40℃ Detector: RI-1530, manufactured by JASCO Corporation

[0058] Preferred examples of linear polyalkylene glycols containing EO units and AO units other than EO include the polyoxyethylene polyoxypropylene glycols No. 1 to 11 shown in Table 1 below.

[0059] [Table 1]

[0060] (Adducts of branched polyhydric alcohols with ethylene oxide and alkylene oxides other than ethylene oxide) Adducts of branched polyhydric alcohols with ethylene oxide and alkylene oxides other than ethylene oxide (hereinafter referred to as "AO adducts of branched polyhydric alcohols other than EO·EO") are obtained by adding ethylene oxide and alkylene oxides other than ethylene oxide to branched polyhydric alcohols.

[0061] The alkylene oxide other than ethylene oxide is not particularly limited and can be arbitrarily selected from alkylene oxides having 3 to 6 carbon atoms, for example, propylene oxide and butylene oxide. The AO other than EO may be one type or a combination of two or more types. For example, the AO other than EO may be propylene oxide, butylene oxide, or a combination of propylene oxide and butylene oxide. Furthermore, the material may further contain alkylene oxides other than propylene oxide and butylene oxide.

[0062] In the molecule of a branched polyhydric alcohol EO·EO-non-EO adduct, the ratio (Q / P) of the number of moles of EO units added (Q) to the number of moles of AO units other than EO units added (P) is preferably 1 or more, more preferably 1.5 or more, and even more preferably 2 or more, from the viewpoint of improving solubility in water. Furthermore, from the viewpoint of the cloud point, the ratio (Q / P) is preferably 19 or less, more preferably 9 or less, and even more preferably 6 or less. The upper and lower limits of these numerical ranges may be combined in any way; for example, the ratio (Q / P) is preferably 1 to 19, more preferably 1.5 to 9, and even more preferably 2 to 6.

[0063] The polyhydric alcohol used as a raw material for branched polyhydric alcohol AO adducts other than EO·EO is not particularly limited as long as it has 3 or more hydroxyl groups, but the number of hydroxyl groups is preferably 3 to 8, more preferably 3 to 6, and even more preferably 3 to 4. Furthermore, from the viewpoint of solubility in water, the polyhydric alcohol used as a raw material for branched polyhydric alcohol AO adducts other than EO·EO preferably has 3 to 10 carbon atoms, more preferably 3 to 6, and even more preferably 3 to 4. Specific examples of the polyhydric alcohol include glycerin, diglycerin, polyglycerin, trimethylolpropane, and pentaerythritol, among which glycerin is preferred.

[0064] The bonding modes of EO and non-EO AO in branched polyhydric alcohol EO·EO-non-AO adducts are not particularly limited, and examples include random bonding (random copolymer), block bonding (block copolymer), graft bonding (graft copolymer), and alternating bonding (alternating copolymer). The block copolymer may be a reverse pluronic block copolymer or a reverse stetronic block copolymer. The bonding modes in branched polyhydric alcohol EO·EO-non-AO adducts may be any of these bonding modes, but from the viewpoint of copolymer manufacturing cost, the random bonding mode is preferred.

[0065] Branched polyhydric alcohol adducts other than EO·EO are preferably water-soluble.

[0066] The mass-average molecular weight (Mw) of branched polyhydric alcohol AO adducts other than EO·EO is preferably 8,000 or more, more preferably 10,000 or more, and even more preferably 12,000 or more, from the viewpoint of sufficiently obtaining the effect of suppressing the cooling rate at 350-150°C. Furthermore, from the viewpoint of viscosity, the mass-average molecular weight of the branched polyhydric alcohol AO adduct other than EO·EO is preferably 50,000 or less, more preferably 40,000 or less, more preferably 30,000 or less, even more preferably 28,000 or less, and even more preferably 25,000 or less. The upper and lower limits of these numerical ranges may be combined arbitrarily. For example, the mass-average molecular weight of branched polyhydric alcohol AO adducts other than EO·EO is preferably 8,000 to 50,000, more preferably 8,000 to 40,000, more preferably 8,000 to 30,000, even more preferably 10,000 to 28,000, and even more preferably 12,000 to 25,000.

[0067] The ratio (Mw / Mn) of the mass-average molecular weight (Mw) to the number-average molecular weight (Mn) of branched polyhydric alcohol AO adducts other than EO·EO is preferably 1.5 to 10, more preferably 2.8 to 9, and even more preferably 2.5 to 5.

[0068] Preferred examples of branched polyhydric alcohol AO adducts other than EO·EO include the EO·PO adduct of glycerin No. 12 and the EO·PO adducts of pentaerythritol Nos. 13-14 (CAS number: 58205-99-5), as shown in Table 2 below.

[0069] [Table 2]

[0070] Component (D) may be used alone or in combination of two or more types. Component (D) may be a combination of linear polyalkylene glycols containing EO units and AO units other than EO, and branched polyhydric alcohols with AO adducts other than EO.

[0071] <Additive (E)> In addition to the components described above, an aqueous heat treatment fluid composition according to one aspect of this disclosure may contain an additive (E) to the extent that it does not impair the effects of this embodiment. Examples of additives (E) include metal deactivators, defoamers, disinfectants, rust inhibitors, and antioxidants, and one or more of these may be used.

[0072] (metal deactivator) Examples of metal deactivators include benzotriazole, imidazoline, pyrimidine derivatives, and thiadiazole, sodium phosphate salts, and phosphate ester derivatives.

[0073] (Antioxidant) Examples of antioxidants include 2,6-ditert-butyl-p-cresol.

[0074] (Preservatives, defoamers, rust inhibitors) Examples of preservatives include diglycolamine, N-methyldicyclohexylamine, 2-amino-2-methyl-1-propanol, N-methyldiethanolamine, cyclohexyldiethanolamine, triethanolamine, 2-(methylamino)ethanol, 2-amino-1-butanol, 2-amino-2-ethyl-1,3-propanediol, and monobutylethanolamine.

[0075] Examples of defoaming agents include silicone compounds and polyether compounds.

[0076] Examples of rust inhibitors include dotecandioic acid and neodecanoic acid.

[0077] Additive (E) may be used alone or in combination of two or more types.

[0078] <Content of each ingredient> (Content of ingredient (A)) The content of component (A) relative to the total amount of the aqueous heat treatment solution composition according to one aspect of this disclosure is not particularly limited. Since the aqueous heat treatment solution composition according to one aspect of this disclosure is sold in a form with a low water content (in the form of a concentrated solution) and can be used by the user after diluting it to the desired concentration, the content of component (A) in the aqueous heat treatment solution composition may change during distribution and use.

[0079] The case in which the aqueous heat treatment liquid composition according to one aspect of this disclosure is in the form of a diluent will be described. In this case, the content of component (A) in the aqueous heat treatment liquid composition is set appropriately from the viewpoint of sufficiently obtaining the gloss improvement effect of component (B); from the viewpoint of sufficiently obtaining the cooling rate suppression effect of component (C), or component (C) and component (D) in combination; and so on.

[0080] For example, the content of component (A) per 100% by mass of the total amount of the aqueous heat treatment liquid composition according to one aspect of the present disclosure is preferably 30% by mass or more, more preferably 35% by mass or more, and even more preferably 40% by mass or more. Furthermore, for example, the content of component (A) relative to 100% by mass of the total amount of the aqueous heat treatment liquid composition according to one aspect of this disclosure is preferably 96% by mass or less, more preferably 92% by mass or less, and even more preferably 88% by mass or less, from the viewpoint of good luster and cooling suppression. The upper and lower limits of these numerical ranges may be combined in any way. For example, the content of component (A) in relation to the total amount of the aqueous heat treatment liquid composition according to one embodiment of the present disclosure, when in the form of a diluted solution, is preferably 30% to 96% by mass, more preferably 35% to 92% by mass, and even more preferably 40% to 88% by mass.

[0081] Next, we will describe the case in which the aqueous heat treatment fluid composition according to one aspect of this disclosure is in the form of a concentrated liquid. In this case, the content of component (A) in the aqueous heat treatment fluid composition according to one aspect of this disclosure is set appropriately from the viewpoint of reducing fire risk and enhancing safety; from the viewpoint of transportation costs; from the viewpoint of concentration handling at the site of use (high degree of freedom to change the concentration range); and from the viewpoint of ensuring sufficient content of components (B), (C), and (D).

[0082] While a lower water content is preferable from the viewpoint of ease of concentration handling at the site of use (higher degree of freedom to change the concentration range), from the viewpoint of reducing fire risk, for example, the content of component (A) per 100% by mass of the total amount of the aqueous heat treatment liquid composition according to one embodiment of this disclosure is preferably 10% by mass or more, and more preferably 15% by mass or more, 20% by mass or more, or 30% by mass or more. Furthermore, for example, the content of component (A) relative to 100% by mass of the total amount of the aqueous heat treatment liquid composition according to one aspect of this disclosure is preferably 65% ​​by mass or less, and more preferably 60% by mass or less, 55% by mass or less, 50% by mass or less, and 45% by mass or less, from the viewpoint of active ingredient concentration. The upper and lower limits of these numerical ranges may be combined in any way. For example, the content of component (A) in relation to the total amount of the aqueous heat treatment liquid composition according to one embodiment of the present disclosure in the form of a concentrated liquid is preferably 10% to 65% by mass, more preferably 15% to 60% by mass, 20% to 55% by mass, 30% to 50% by mass, and even more preferably 30% to 45% by mass.

[0083] (Content of ingredient (B)) From the viewpoint of enhancing the gloss-improving effect, the content of component (B) per 100% by mass of the total amount of the aqueous heat treatment liquid composition according to one aspect of this disclosure is preferably 0.5% by mass or more, more preferably 1% by mass or more, and even more preferably 1.5% by mass or more. Furthermore, from the viewpoint of the solubility of component (B), the content of component (B) in the aqueous heat treatment liquid composition according to one aspect of this disclosure is preferably 15% by mass or less, more preferably 12% by mass or less, even more preferably 9% by mass or less, and even more preferably 8% by mass or less. The upper and lower limits of these numerical ranges may be combined in any way. For example, the content of component (B) relative to 100% by mass of the total amount of the aqueous heat treatment liquid composition according to one embodiment of the present disclosure in the form of a diluted solution is preferably 0.5% to 15% by mass, more preferably 1% to 12% by mass, even more preferably 1.5% to 9% by mass, and even more preferably 1.5% to 8% by mass.

[0084] (Content of ingredient (C)) The content of component (C) in a aqueous heat treatment liquid composition according to one aspect of this disclosure is preferably 3% by mass or more, more preferably 4% by mass or more, even more preferably 5% by mass or more, and even more preferably 6% by mass or more, from the viewpoint of enhancing the effect of suppressing the cooling rate and enhancing the solubility of component (B). Furthermore, from the viewpoint of the manufacturing cost of the aqueous heat treatment liquid composition according to one aspect of this disclosure, the content of component (C) per 100% by mass of the total amount is preferably 40% by mass or less, more preferably 30% by mass or less, and even more preferably 25% by mass or less. The upper and lower limits of these numerical ranges may be combined in any way. For example, the content of component (C) relative to 100% by mass of the total amount of the aqueous heat treatment liquid composition according to one embodiment of the present disclosure, when in the form of a diluted solution, is preferably 3% to 40% by mass, more preferably 4% to 30% by mass, even more preferably 5% to 25% by mass, and even more preferably 6% to 25% by mass.

[0085] (Content of ingredient (D)) The content of component (D) in the aqueous heat treatment liquid composition according to one aspect of this disclosure is preferably 0.5% by mass or more, more preferably 1% by mass or more, and even more preferably 1.5% by mass or more, from the viewpoint of enhancing the effect of suppressing the cooling rate. Furthermore, the content of component (D) in the total amount of the aqueous heat treatment liquid composition according to one aspect of this disclosure is preferably 20% by mass or less, more preferably 15% by mass or less, even more preferably 10% by mass or less, and even more preferably 8% by mass or less, from the viewpoint of the solubility of component (B). The upper and lower limits of these numerical ranges may be combined in any way. For example, the content of component (C) relative to 100% by mass of the total amount of the aqueous heat treatment liquid composition according to one embodiment of the present disclosure in the form of a diluted solution is preferably 0.5% to 20% by mass, more preferably 1% to 15% by mass, even more preferably 1.5% to 10% by mass, and even more preferably 1.5% to 8% by mass.

[0086] (C / D ratio) Furthermore, the content of component (D) is preferably determined considering the content of component (C). The preferred numerical range for the C / D ratio can be set to obtain the desired effect depending on the molecular weight of component (D) used, the ratio of the number of moles of AO units added in the molecule (Q / P) (e.g., EO / PO ratio), the molecular structure (linear or branched), etc. However, a larger C / D ratio tends to increase storage stability, while a smaller C / D ratio tends to increase the cooling suppression effect. For example, from the viewpoint of improving the storage stability of the aqueous heat treatment liquid composition, the ratio of the content of component (C) to the content of component (D) (C / D) is preferably 2 or more by mass ratio, more preferably 2.3 or more, even more preferably 3 or more, and even more preferably 3.5 or more. Furthermore, from the viewpoint of enhancing the cooling rate suppression effect, the ratio of the content of component (C) to the content of component (D) (C / D) is preferably 10 or less by mass, more preferably 8 or less, and even more preferably 6 or less. The upper and lower limits of these numerical ranges may be combined in any way. For example, the ratio of the content of component (C) to the content of component (D) (C / D) is preferably 2 to 10 by mass, more preferably 2.3 to 10, even more preferably 3 to 8, and even more preferably 3.5 to 6.

[0087] (Content of components (B), (C), and (D) in the concentrated solution) The amounts of components (B), (C), and (D) in the concentrated solution are set appropriately, taking into consideration the concentration ratio of the concentrated solution and the balance of the amounts of the three components (B) to (D), so that the amount of each component when diluted falls within the range described above.

[0088] When the aqueous heat treatment liquid composition according to one aspect of this disclosure is in the form of a concentrated liquid, for example, from the viewpoint of enhancing the luster-improving effect, the content of component (B) is preferably 2% by mass or more, more preferably 3% by mass or more, and even more preferably 4% by mass or more, when the total amount of components (B), (C), and (D) is 100% by mass. Furthermore, from the viewpoint of solubility, the content of component (B) is preferably 30% by mass or less, more preferably 25% by mass or less, even more preferably 20% by mass or less, and even more preferably 15% by mass or less, when the total amount of components (B), (C), and (D) is taken as 100% by mass. The upper and lower limits of these numerical ranges may be combined arbitrarily. For example, in the case of a concentrated liquid, the content of component (B) is preferably 2% to 30% by mass, more preferably 2% to 25% by mass, even more preferably 3% to 20% by mass, and even more preferably 4% to 15% by mass, when the total amount of components (B), (C), and (D) is 100% by mass.

[0089] Furthermore, for example, from the viewpoint of the solubility of component (B), the content of component (C) is preferably 5% by mass or more, more preferably 10% by mass or more, even more preferably 15% by mass or more, and even more preferably 20% by mass or more, when the total amount of components (B), components (C), and components (D) is taken as 100% by mass. Furthermore, from the viewpoint of the manufacturing cost of the composition, the content of component (C) is preferably 80% by mass or less, more preferably 70% by mass or less, even more preferably 65% ​​by mass or less, and even more preferably 60% by mass or less, when the total amount of components (B), (C), and (D) is taken as 100% by mass. The upper and lower limits of these numerical ranges may be combined in any way. For example, in the case of a concentrated liquid, the content of component (C) is preferably 5% to 80% by mass, more preferably 10% to 70% by mass, even more preferably 15% to 65% by mass, and even more preferably 20% to 60% by mass, when the total amount of components (B), (C), and (D) is 100% by mass.

[0090] Furthermore, for example, from the viewpoint of suppressing cooling during dilution, the content of component (D) is preferably 2% by mass or more, more preferably 5% by mass or more, even more preferably 6% by mass or more, even more preferably 7% by mass or more, and even more preferably 8% by mass or more, when the total amount of components (B), components (C), and components (D) is 100% by mass. Furthermore, from the viewpoint of the solubility of component (B), the content of component (D) is preferably 35% by mass or less, more preferably 30% by mass or less, and even more preferably 25% by mass or less, when the total amount of components (B), (C), and (D) is taken as 100% by mass. The upper and lower limits of these numerical ranges may be combined arbitrarily. For example, in the case of a concentrated liquid, the content of component (D) is preferably 2% to 35% by mass, more preferably 5% to 35% by mass, even more preferably 6% to 30% by mass, even more preferably 7% to 25% by mass, and even more preferably 8% to 25% by mass, when the total amount of components (B), (C), and (D) is 100% by mass.

[0091] (Content of component (E)) The content of component (E) in the aqueous heat treatment liquid composition according to one aspect of this disclosure can be appropriately determined within a range that does not impede the effects of this embodiment and within a range that allows the effects of component (E) to be exerted.

[0092] When the aqueous heat treatment solution composition according to one aspect of this disclosure is in the form of a diluent, the content of component (E) is not particularly limited, but is preferably 0.01 to 10% by mass, more preferably 0.05 to 7.5% by mass, and even more preferably 0.1 to 5% by mass, based on 100% by mass of the total amount of the aqueous heat treatment solution composition.

[0093] Furthermore, the content of component (E) when the aqueous heat treatment liquid composition according to one aspect of this disclosure is in the form of a concentrated liquid is not particularly limited. The content of component (E) relative to 100% by mass of the total amount of the aqueous heat treatment liquid composition can be determined according to the concentration ratio of the concentrated liquid so that the content of component (E) when diluted falls within the range described above. For example, the content of component (E) is preferably 0.1 to 15% by mass, more preferably 0.5 to 10% by mass, and even more preferably 1 to 5% by mass, relative to 100% by mass of the total amount of the aqueous heat treatment liquid composition. If the aqueous heat treatment liquid composition according to one aspect of this disclosure contains multiple components as component (E), each component shall be contained independently within the above range.

[0094] <Preferred formulation example> An aqueous heat treatment fluid composition according to one embodiment of the present disclosure contains component (A), component (B), and component (C), and optionally contains component (D), When the total amount of the aqueous heat treatment fluid composition is assumed to be 100% by mass, The aforementioned component (B) is 0.5% by mass or more and 15% by mass or less, The aforementioned component (C) is 3% by mass or more and 40% by mass or less, The aforementioned component (D) is 0.5% by mass or more and 20% by mass or less, It is preferable that it includes.

[0095] Furthermore, an aqueous heat treatment fluid composition according to another embodiment of this disclosure contains component (A), component (B), and component (C), and optionally contains component (D), When the total amount of the aqueous heat treatment fluid composition is assumed to be 100% by mass, The aforementioned component (B) is 1.5% by mass or more and 8% by mass or less, The aforementioned component (C) is 3% by mass or more and 25% by mass or less, The aforementioned component (D) is 0.5% by mass or more and 10% by mass or less, It is preferable that it includes.

[0096] <Properties of aqueous heat treatment solution compositions> (Photoluminescence) A water-based heat treatment liquid composition according to one aspect of this disclosure preferably exhibits improved surface luster of a metal material quenched or tempered using the composition, compared to a water-based heat treatment liquid composition that does not contain component (B), and more preferably exhibits good surface luster of a metal material quenched or tempered using the composition. For example, it is preferable that the luster evaluation result, as evaluated by the evaluation method described in the examples below, is "somewhat good" or "good," and more preferably "good."

[0097] (cooling rate) The aqueous heat treatment fluid composition according to one aspect of this disclosure preferably exhibits a suppressed (slower) cooling rate compared to an aqueous heat treatment fluid composition that does not contain components (C) and (D). The degree to which the cooling rate of the aqueous heat treatment fluid composition according to one aspect of this disclosure is suppressed is not particularly limited.

[0098] The cooling rate of the aqueous heat treatment liquid composition according to one aspect of this disclosure is preferably less than 400°C / s, more preferably 300°C / s or less, and even more preferably 250°C / s or less, at 350-150°C. An aqueous heat treatment liquid composition having a cooling rate of less than 400°C / s at 350-150°C can be said to have a suppressed (slow) cooling rate. Furthermore, there are no particular limitations on the lower limit of the 350-150°C cooling rate using the aqueous heat treatment liquid composition according to one aspect of this disclosure, but for example, it is 30°C / s or higher. The upper and lower limits of these numerical ranges may be combined in any way. For example, the 350-150°C cooling rate of the aqueous heat treatment liquid composition according to one aspect of this disclosure is preferably 30°C / s or more and less than 400°C / s, more preferably 30°C / s to 300°C / s, and even more preferably 30°C / s to 250°C / s.

[0099] (Storage stability) The aqueous heat treatment liquid composition according to one aspect of this disclosure preferably has good storage stability. For example, it is preferable that the storage stability evaluation result, as evaluated by the evaluation method described in the examples below, is "good".

[0100] <Form of aqueous heat treatment liquid composition> The aqueous heat treatment fluid composition according to one aspect of this disclosure may be prepared by blending the above-mentioned components at the desired concentration at the time of use from the beginning, or a concentrated solution (stock solution) may be prepared first and then diluted with water to the desired concentration at the time of use. The aqueous heat treatment fluid composition according to one aspect of this disclosure also has good storage stability in the form of a concentrated solution. For this reason, considering the reduction of transportation costs and the ability to adjust the cooling performance by dilution concentration, the aqueous heat treatment fluid composition according to one aspect of this disclosure is preferably in the form of a concentrated solution.

[0101] As a concentrated aqueous heat treatment liquid composition according to one aspect of this disclosure, from the viewpoint of ease of handling, the aqueous heat treatment liquid composition is concentrated by a volume ratio of preferably 2 to 20 times, more preferably 2.5 to 15 times, and even more preferably 3 to 10 times.

[0102] <Method for producing an aqueous heat treatment liquid composition> An aqueous heat treatment fluid composition according to one aspect of this disclosure can be manufactured by mixing the above-described components. The mixing method is not particularly limited as long as the components can be mixed uniformly.

[0103] [2. Methods for manufacturing metal materials] A method for manufacturing a metal material according to one aspect of the present disclosure includes a heat treatment step for the metal material, wherein an aqueous heat treatment liquid composition according to one aspect of the present disclosure is used as a coolant for cooling the heated metal material in the heat treatment step.

[0104] According to a method for manufacturing a metal material according to one aspect of this disclosure, since an aqueous heat treatment liquid composition according to one aspect of this disclosure is used as a coolant to cool the heated metal material in the heat treatment process, it is possible to manufacture a metal material that has good luster after heat treatment and suppresses distortion and quench cracking.

[0105] In a method for manufacturing a metal material according to one aspect of the present invention, the specific type of metal material to be manufactured is not particularly limited.

[0106] The type of heat treatment step for a metal material included in a method for manufacturing a metal material according to one aspect of this disclosure is not limited. Examples of the heat treatment step include a quenching step and a tempering step. In a method for manufacturing a metal material according to one aspect of this disclosure, an aqueous heat treatment liquid composition according to one aspect of this disclosure is used in the heat treatment step. The method for manufacturing a metal material according to one aspect of this disclosure may include only a quenching step, only a tempering step, or both a quenching step and a tempering step as the heat treatment step. If the method for manufacturing a metal material according to one aspect of this disclosure includes both a quenching step and a tempering step as the heat treatment step, the tempering step may be included after the quenching step. If the method for manufacturing a metal material according to one aspect of this disclosure includes a tempering step after the quenching step, it is preferable to use the aqueous heat treatment liquid composition according to one aspect of this disclosure as a coolant to cool the metal material after tempering in the tempering step.

[0107] In the heat treatment process, the method of heating the metal material is not particularly limited, and conventionally known heating methods such as high-frequency induction hardening and carburizing can be used. Furthermore, in the quenching process, the cooling method using the aqueous heat treatment liquid composition is not particularly limited, and cooling methods employed in conventionally known quenching methods can also be employed in this embodiment. For example, an immersion method may be employed in which the heated metal material is immersed in the aqueous heat treatment liquid composition according to one aspect of this disclosure described above to cool it, or an injection method may be employed in which the aqueous heat treatment liquid composition according to one aspect of this disclosure described above is sprayed onto the heated metal material to cool it.

[0108] A method for manufacturing a metallic material according to one aspect of this disclosure may further include steps other than the heat treatment step.

[0109] [3. Manufacturing equipment for metal materials] A metal material manufacturing apparatus according to one aspect of the present disclosure is a metal material manufacturing apparatus that performs at least a heat treatment step for a metal material, wherein in the heat treatment step, an aqueous heat treatment liquid composition according to one aspect of the present disclosure is used as a coolant to cool the heated metal material.

[0110] According to a metal material manufacturing apparatus according to one aspect of the present disclosure, since an aqueous heat treatment liquid composition according to one aspect of the present disclosure is used as a coolant to cool the heated metal material in the heat treatment process, it is possible to manufacture a metal material that has good luster after heat treatment and suppresses distortion and quench cracking.

[0111] In a metal material manufacturing apparatus according to one aspect of the present invention, the specific type of metal material to be manufactured is not particularly limited.

[0112] The type of heat treatment process for a metal material carried out in a metal material manufacturing apparatus according to one aspect of this disclosure is not limited. Examples of such heat treatment processes include quenching and tempering. In the metal material manufacturing apparatus according to one aspect of this disclosure, an aqueous heat treatment liquid composition according to one aspect of this disclosure is used in the heat treatment process. The metal material manufacturing apparatus according to one aspect of this disclosure may carry out only a quenching process, only a tempering process, or both a quenching and tempering process as the heat treatment process. When the metal material manufacturing apparatus according to one aspect of this disclosure carries out both a quenching and tempering process as the heat treatment process, the tempering process may be carried out after the quenching process. When the metal material manufacturing apparatus according to one aspect of this disclosure includes a tempering process after the quenching process, it is preferable to use the aqueous heat treatment liquid composition according to one aspect of this disclosure as a coolant for cooling the metal material after tempering in the tempering process.

[0113] A manufacturing apparatus for a metallic material according to one aspect of this disclosure comprises at least a heat treatment apparatus for performing a heat treatment process on the metallic material. The specific configuration of the heat treatment apparatus is not particularly limited. Depending on the type of heating and cooling method used in the heat treatment process to be performed (e.g., quenching process, tempering process), the heat treatment apparatus may be equipped with a mechanism capable of performing these methods. The heating and cooling methods in the heat treatment process are as described in the manufacturing method for a metallic material according to one aspect of this disclosure.

[0114] A metal material manufacturing apparatus according to one aspect of this disclosure may further include components other than a heat treatment apparatus.

[0115] 〔summary〕 The aqueous heat treatment liquid composition according to Embodiment 1 of the present invention comprises water (A), condensed phosphate (B), and glycols (C).

[0116] The aqueous heat treatment liquid composition according to aspect 2 of the present invention may further contain polyalkylene glycols (D) having a molecular weight greater than that of glycols (C) and comprising repeating units derived from ethylene oxide and repeating units derived from alkylene oxides other than ethylene oxide.

[0117] In the aqueous heat treatment liquid composition according to embodiment 3 of the present invention, the condensed phosphate (B) may be a pyrophosphate in the configuration described in embodiment 1 or 2 above.

[0118] The aqueous heat treatment liquid composition according to embodiment 4 of the present invention may be configured such that, in any one of embodiments 1 to 3 above, the number average molecular weight of the glycols (C) is 1,000 or less.

[0119] In the aqueous heat treatment liquid composition according to aspect 5 of the present invention, the polyalkylene glycol (D) containing repeating units derived from ethylene oxide and repeating units derived from alkylene oxide other than ethylene oxide may have a mass-average molecular weight of 8,000 or more, as described in aspect 2 above.

[0120] In any one of the above embodiments 1 to 5, the aqueous heat treatment liquid composition according to embodiment 6 of the present invention may be configured such that the glycols (C) are at least one selected from the group consisting of polypropylene glycol, propylene glycol, polyethylene glycol, ethylene glycol, and derivatives thereof.

[0121] The aqueous heat treatment liquid composition according to embodiment 7 of the present invention may be configured such that, in embodiment 2 or 5 above, the ratio (Q / P) of the number of moles of ethylene oxide units added (Q) to the number of moles of alkylene oxide units other than ethylene oxide added (P) in a molecule of polyalkylene glycols (D) containing repeating units derived from ethylene oxide and repeating units derived from alkylene oxides other than ethylene oxide is 1 or more and 19 or less.

[0122] In the aqueous heat treatment liquid composition according to embodiment 8 of the present invention, in embodiment 2, 5, or 7 above, the ratio (C / D) of the content of glycols (C) to the content of polyalkylene glycols (D) containing repeating units derived from ethylene oxide and repeating units derived from alkylene oxides other than ethylene oxide is 2.3 or more and 10 or less by mass ratio.

[0123] The aqueous heat treatment liquid composition according to aspect 9 of the present invention may contain, in any one of aspects 1 to 8 above, water (A), condensed phosphate (B), and glycols (C), and optionally contain polyalkylene glycols (D) which include repeating units derived from ethylene oxide and repeating units derived from alkylene oxides other than ethylene oxide, and when the total amount of condensed phosphate (B), glycols (C), and polyalkylene glycols (D) which include repeating units derived from ethylene oxide and repeating units derived from alkylene oxides other than ethylene oxide is taken as 100% by mass, the composition may include 2% by mass or more and 30% by mass or less of condensed phosphate (B), 5% by mass or more and 80% by mass or less of glycols (C), and 2% by mass or more and 35% by mass or less of polyalkylene glycols (D) which include repeating units derived from ethylene oxide and repeating units derived from alkylene oxides other than ethylene oxide.

[0124] The aqueous heat treatment liquid composition according to aspect 10 of the present invention may contain, in any one of the above aspects 1 to 8, water (A), condensed phosphate (B), and glycols (C), and optionally contain polyalkylene glycols (D) which include repeating units derived from ethylene oxide and repeating units derived from alkylene oxides other than ethylene oxide, and when the total amount of the aqueous heat treatment liquid composition is 100% by mass, the composition may contain 0.5% by mass or more and 15% by mass or less of the condensed phosphate (B), 3% by mass or more and 40% by mass or less of the glycols (C), and 0.5% by mass or more and 20% by mass or less of the polyalkylene glycols (D) which include repeating units derived from ethylene oxide and repeating units derived from alkylene oxides other than ethylene oxide.

[0125] A method for producing a metal material according to aspect 11 of the present invention may include a heat treatment step for the metal material, wherein the aqueous heat treatment liquid composition described in any one of aspects 1 to 10 above may be used as a coolant for cooling the heated metal material in the heat treatment step.

[0126] An apparatus for producing a metal material according to aspect 12 of the present invention is an apparatus for producing a metal material that performs at least a heat treatment step of a metal material, wherein in the heat treatment step, the aqueous heat treatment liquid composition according to any one of aspects 1 to 10 above is used as a coolant for cooling a heated metal material. The configuration may be as such.

[0127] The present disclosure is not limited to the embodiments described above, and various modifications can be made within the scope recited in the claims, and embodiments obtained by appropriately combining the technical means respectively disclosed in the embodiments are also included in the technical scope of the present disclosure.

Examples

[0128] Hereinafter, the present invention will be described in further detail with reference to examples and comparative examples, but the present invention is not limited to these examples.

[0129] [Test Example 1] 1. Materials The following materials were used for the aqueous heat treatment liquid compositions of the examples and comparative examples. <Water (A): Component (A)> • Tap water <Condensed phosphate (B): Component (B)> • Potassium pyrophosphate (manufactured by Ohira Chemical Industry Co., Ltd., product name: Potassium pyrophosphate) <Glycols (C): Component (C)> • Propylene glycol (manufactured by AGC Inc., product name: Propylene glycol, polypropylene glycol with a degree of polymerization of 1, molecular weight 76.09 g / mol) <Polyalkylene glycols (D) containing repeating units derived from EO and repeating units derived from AO other than EO: Component (D)> • Linear polyalkylene glycol 1 containing EO units and PO units (linear PAG1) (random polymerization, Mw=17,000, Mn=7,700, Mw / Mn=2.2, EO / PO ratio (molar ratio)=4.0) • Branched polyhydric alcohol EO·PO adduct 1 (branched PAG1) (mixed adduct of EO and PO of glycerin, Mw=21,000, Mn=11,000, Mw / Mn=1.9, EO / PO ratio (molar ratio)=2.6)

[0130] 2. Preparation The aqueous heat treatment fluid compositions (undiluted solutions) for Examples 1-3 and Comparative Example 1 were prepared with the compositions shown in Table 3. A blank space in Table 3 indicates that the component was not added.

[0131] 3. Evaluation The storage stability of the aqueous heat treatment solution compositions (undiluted solutions) of Examples 1-3 and Comparative Example 1 was evaluated. In addition, the luster and cooling properties of the diluted solutions obtained by diluting the aqueous heat treatment solution compositions (undiluted solutions) of Examples 1-3 and Comparative Example 1 with water to the predetermined dilution ratios shown in Table 4 were evaluated.

[0132] 3-1. Storage Stability The aqueous heat treatment solution compositions (undiluted solutions) of Examples 1-3 and Comparative Example 1 were left to stand at room temperature, and the separation state was visually confirmed after one week.

[0133] Products in which no layer separation was observed visually were evaluated as having good storage stability.

[0134] 3-2. Brightness The glossiness of steel materials after quenching was evaluated based on the report "Influence of Oxygen in Heat Treatment Oil Baths on Brightness (Idemitsu Tribo Review, No. 31, pp. 1963-1966, published September 30, 2008)".

[0135] Specifically, a dumbbell-shaped steel material S45C (diameter: 16 mm, length: 30 mm, hardness HRC: 16) and a cylindrical steel material SUJ2 (diameter: 10 mm, length: 30 mm, hardness HRC: 15) were combined to form a test specimen. In detail, the dumbbell-shaped steel material S45C and the cylindrical steel material SUJ2 were tied together at the center using SUS303 wire (see Figure 1). The test specimen was then heated in a furnace with a mixed gas atmosphere of nitrogen and hydrogen, and then quenched by immersion in the aqueous heat treatment solution composition of the example or comparative example to perform a quenching test.

[0136] The following four conditions were used for the hardening test. (Heat treatment test conditions) Furnace temperature: 850℃ Specimen holding time in the furnace: 40 minutes after the furnace temperature reaches 850°C. Temperature of aqueous heat treatment solution composition: 30°C Immersion time (quenching time) of the test specimen in the aqueous heat treatment solution composition: 10 minutes.

[0137] For the test specimens after quenching, the luster was evaluated based on the following criteria, focusing on "brightness." (brightness) Appearance samples with predetermined coloring were prepared and visually compared and evaluated against the color of the test specimens after quenching. The degree of coloring of the appearance samples is indicated by the numerical values ​​shown below. 0: No coloring at all. 1: There is a slight coloring. 2: It is colored. 3: It has a strong coloring.

[0138] A numerical value representing the degree of coloring of the test piece after quenching was evaluated as poor luster if it was 3, slightly poor luster if it was 2, slightly good luster if it was 1, and good luster if it was 0.

[0139] 3-3. Cooling property In accordance with the cooling performance test method (Method B: core temperature measurement method) for water-soluble quenching solutions specified in JIS K2242:2012, a silver rod heated to 810°C was immersed in a water-based heat treatment solution composition (liquid temperature: 30°C), and the cooling curve of the silver rod was determined. Based on this cooling curve, the cooling rate (350-150°C cooling rate (°C / s)) when the silver rod cooled from 350°C to 150°C was calculated.

[0140] 4.Results Table 3 shows the evaluation results for storage stability, and Table 4 shows the evaluation results for brilliance and coolability. Figure 1 shows the appearance of the test specimens after quenching using each of the aqueous heat treatment liquid compositions (diluted solutions) in Examples 1-3 and Comparative Example 1.

[0141] [Table 3]

[0142] [Table 4]

[0143] As shown in Table 3, the aqueous heat treatment liquid compositions of Examples 1 to 3 did not undergo layer separation over time and exhibited good storage stability.

[0144] Furthermore, the results in Table 3 show that the aqueous heat treatment fluid compositions of Examples 1 to 3 exhibited a more suppressed 350-150°C cooling rate than the aqueous heat treatment fluid composition of Comparative Example 1, which did not contain components (C) and (D). Additionally, the results in Example 3 indicate that when the aqueous heat treatment fluid composition contains component (D), the suppression effect on the 350-150°C cooling rate tended to increase as the concentrations of components (B), (C), and (D) increased.

[0145] [Test Example 2] 1.Material In addition to the materials used in Test Example 1, the following materials were used as materials for the aqueous heat treatment solution compositions in the examples and comparative examples. <Ingredient (D)> • Linear polyalkylene glycols 2 (linear PAG2) containing EO and PO units (random polymerization, Mw=11,000, Mn=8,200, Mw / Mn=1.3, EO / PO ratio (molar ratio)=6.7)

[0146] 2. Preparation The aqueous heat treatment fluid compositions (stock solutions) for Examples 4-6 and Comparative Examples 2-13 were prepared with the compositions shown in Tables 5-7. A blank space in Tables 5-7 indicates that the component was not added.

[0147] 3. Evaluation The storage stability of the aqueous heat treatment liquid compositions (undiluted solutions) of Examples 4-6 and Comparative Examples 2-13 was evaluated as described above.

[0148] 4.Results The results of the storage stability evaluation are shown in Tables 5-7.

[0149] [Table 5]

[0150] [Table 6]

[0151] [Table 7]

[0152] As shown in Table 5, the aqueous heat treatment fluid compositions of Examples 4-6 did not undergo layer separation over time and exhibited good storage stability. Furthermore, a comparison of Examples 4-5 with Comparative Example 13 revealed that the presence of component (C) in the aqueous heat treatment fluid composition suppressed layer separation even when component (D) was further added. Additionally, a comparison of Examples 4-5 with Comparative Examples 2-10 revealed that a higher C / D ratio (the ratio of component (C) to component (D)) tended to result in better storage stability.

[0153] [Test Example 3] 1.Material The following condensed phosphates were used in the preparation of the aqueous heat treatment solution composition in the reference example. • Potassium pyrophosphate (manufactured by Ohira Chemical Industry Co., Ltd., product name: Potassium pyrophosphate) • Sodium pyrophosphate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., product name: Sodium pyrophosphate)

[0154] Furthermore, as inorganic salts of a different type from condensed phosphates, the following inorganic salts were used in the preparation of the comparative aqueous heat treatment solution composition. • Sodium nitrite (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., product name: Sodium Nitrite) • Sodium sulfite (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., product name: Sodium Sulfite) • Ammonium nitrate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., product name: Ammonium nitrate) • Potassium carbonate (manufactured by Takasugi Pharmaceutical Co., Ltd., product name: Takasugi Grade 1 Potassium Carbonate) • Ammonium sulfate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., product name: Ammonium sulfate) • Sodium tetraborate (manufactured by Junsei Chemical Co., Ltd., product name: Sodium tetraborate decahydrate) • Potassium dihydrogen citrate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., product name: Potassium dihydrogen citrate) • Anionic carboxylic acid (manufactured by Sanyo Chemical Industries, Ltd., product name: Sanhibiter No. 2-1, anionic surfactant) • Disodium hydrogen phosphate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., product name: Disodium hydrogen phosphate) • Polyoxyethylene alkyl ether phosphate (CAS number: 9046-01-9) (manufactured by Toho Chemical Industry Co., Ltd., product name: Phosphanol RS-410)

[0155] 2. Preparation The aqueous heat treatment fluid compositions (diluted solutions) for Reference Examples 1 to 7 were prepared with the compositions shown in Table 8. In the aqueous heat treatment fluid compositions (diluted solutions) for Reference Examples 1 to 7, the concentration of condensed phosphate was changed in steps.

[0156] Furthermore, aqueous heat treatment fluid compositions (diluted solutions) for Comparative Examples 14-23 were prepared with the compositions shown in Table 9. In the aqueous heat treatment fluid compositions (diluted solutions) for Comparative Examples 14-23, a different type of inorganic salt was used instead of condensed phosphate. In Comparative Example 24, water was used. Note that blanks in Tables 8-9 indicate that the component was not added.

[0157] 3. Evaluation The glossiness described above was evaluated for the aqueous heat treatment fluid compositions (diluted solutions) of Reference Examples 1 to 7, the aqueous heat treatment fluid compositions (diluted solutions) of Comparative Examples 14 to 23, and water in Comparative Example 24.

[0158] 4.Results The evaluation results for glossiness are shown in Tables 8 and 9. Figure 2 shows the appearance of test specimens after quenching using each of the aqueous heat treatment solution compositions (dilutions) for Reference Examples 1 to 7 and Comparative Examples 14 to 23, as well as water for Comparative Example 24.

[0159] [Table 8]

[0160] [Table 9]

[0161] As shown in Tables 8-9, the addition of condensed phosphates to inorganic salts improved luster. Furthermore, from the results of Reference Examples 1-7 in Table 8, the luster-improving effect tended to weaken at lower concentrations of condensed phosphates, but compared to Comparative Examples 14-24 which did not contain condensed phosphates, the luster was improved. [Industrial applicability]

[0162] A water-based heat treatment fluid composition according to one aspect of this disclosure can be used as a quenching or tempering fluid for metal materials.

Claims

1. A water-based heat treatment solution composition containing water (A), condensed phosphate (B), and glycols (C).

2. The aqueous heat treatment liquid composition according to claim 1, further comprising polyalkylene glycols (D) having a molecular weight greater than that of glycols (C), and containing repeating units derived from ethylene oxide and repeating units derived from alkylene oxides other than ethylene oxide.

3. The aqueous heat treatment liquid composition according to claim 1 or 2, wherein the condensed phosphate (B) is a pyrophosphate.

4. The aqueous heat treatment liquid composition according to any one of claims 1 to 3, wherein the number average molecular weight of the glycols (C) is 1,000 or less.

5. The aqueous heat treatment liquid composition according to claim 2, wherein the polyalkylene glycol (D), which includes repeating units derived from ethylene oxide and repeating units derived from alkylene oxide other than ethylene oxide, has a mass-average molecular weight of 8,000 or more.

6. The aqueous heat treatment liquid composition according to any one of claims 1 to 5, wherein the glycols (C) are at least one selected from the group consisting of polypropylene glycol, propylene glycol, polyethylene glycol, ethylene glycol, and derivatives thereof.

7. The aqueous heat treatment liquid composition according to claim 2 or 5, wherein the ratio (Q / P) of the number of moles of ethylene oxide units added (Q) to the number of moles of alkylene oxide units other than ethylene oxide added (P) in a molecule of polyalkylene glycols (D) containing repeating units derived from ethylene oxide and repeating units derived from alkylene oxides other than ethylene oxide is 1 or more and 19 or less.

8. The aqueous heat treatment liquid composition according to claim 2, 5, or 7, wherein the ratio (C / D) of the content of glycols (C) to the content of polyalkylene glycols (D) containing repeating units derived from ethylene oxide and repeating units derived from alkylene oxides other than ethylene oxide is 2.3 or more and 10 or less by mass ratio.

9. The following is a description of a substance containing water (A), condensed phosphate (B), and glycols (C): The polyalkylene glycol (D) optionally contains repeating units derived from ethylene oxide and repeating units derived from alkylene oxides other than ethylene oxide, When the total amount of the condensed phosphate (B), the glycols (C), and polyalkylene glycols (D) containing repeating units derived from ethylene oxide and repeating units derived from alkylene oxides other than ethylene oxide is taken as 100% by mass, The aforementioned condensed phosphate (B) is present in an amount of 2% by mass or more and 30% by mass or less, The aforementioned glycols (C) are 5% by mass or more and 80% by mass or less, Polyalkylene glycols (D) containing repeating units derived from ethylene oxide and repeating units derived from alkylene oxides other than ethylene oxide, in an amount of 2% by mass or more and 35% by mass or less, An aqueous heat treatment liquid composition according to any one of claims 1 to 8, comprising the above.

10. The following is a description of a substance containing water (A), condensed phosphate (B), and glycols (C): The polyalkylene glycol (D) optionally contains repeating units derived from ethylene oxide and repeating units derived from alkylene oxides other than ethylene oxide, When the total amount of the aqueous heat treatment fluid composition is 100% by mass, The aforementioned condensed phosphate (B) is 0.5% by mass or more and 15% by mass or less, The aforementioned glycols (C) are 3% by mass or more and 40% by mass or less, Polyalkylene glycols (D) containing repeating units derived from ethylene oxide and repeating units derived from alkylene oxides other than ethylene oxide, in an amount of 0.5% by mass or more and 20% by mass or less, An aqueous heat treatment liquid composition according to any one of claims 1 to 8, comprising the above.

11. This includes a heat treatment process for metal materials. A method for producing a metal material, wherein in the heat treatment step, the aqueous heat treatment liquid composition described in any one of claims 1 to 10 is used as a coolant for cooling the heated metal material.

12. A manufacturing apparatus for metal materials that performs at least a heat treatment process for metal materials, A metal material manufacturing apparatus that uses the aqueous heat treatment liquid composition described in any one of claims 1 to 10 as a coolant for cooling the heated metal material in the heat treatment process.

Images