Iron-based high-temperature alloy wire rod for cold heading and surface treatment process of iron-based high-temperature alloy wire rod

Abstract

The invention discloses an iron-based high-temperature alloy wire for cold heading and a surface treatment process thereof, and relates to the technical field of alloy materials.The preparation process comprises the following steps that iron-based high-temperature alloy is smelted and hot-rolled to obtain a hot-rolled wire rod, after surface oxide skin is removed through hydrochloric acid pickling, the temperature is increased to 900 DEG C, heat preservation is conducted for 2 h, then water cooling is conducted, and surface cleaning is conducted through absolute ethyl alcohol; the method comprises the following steps of: soaking the iron-based high-temperature alloy wire into a composite lubricant, drying, carrying out rough drawing and cold drawing, carrying out solution treatment and multi-section aging treatment to obtain the iron-based high-temperature alloy wire, and carrying out surface acid pickling and copper plating and fine drawing and cold drawing to obtain the iron-based high-temperature alloy wire for cold heading after surface treatment.

Description

Technical Field

[0001] The invention relates to the technical field of alloy materials, in particular to an iron-based high-temperature alloy wire for cold heading and a surface treatment process thereof. Background Art

[0002] As an efficient and energy-saving metal forming process, cold heading is mainly used to manufacture high-strength bolts, nuts, pins and other fasteners, and is highly respected in the modern manufacturing industry. With the advancement of industrial technology and the growth of market demand, the requirements for fasteners are getting higher and higher. Compared with nickel-based and cobalt-based alloys, iron-based high-temperature alloys have lower costs and meet large-scale production applications. They are widely used as fastener materials. Fasteners are mostly cold-processed with wire before cold heading. However, most wire products on the market are of varying quality. The cold heading materials produced have unstable performance and are prone to cracks on the surface. The wires fail to meet the quality requirements of high-strength fasteners and have a high scrap rate, resulting in high manufacturing costs and insufficient economy. Despite the rapid development of the cold heading steel industry, high-performance quality cold heading steel wire still faces certain market gaps and technical challenges. Summary of the invention

[0003] The object of the present invention is to provide an iron-based high-temperature alloy wire for cold heading and a surface treatment process thereof, so as to solve the problems raised in the prior art.

[0004] To achieve the above object, the present invention provides the following technical solutions: An iron-based high-temperature alloy wire for cold heading and a surface treatment process thereof, comprising the following process steps: Step 1: The iron-based high-temperature alloy is smelted and hot-rolled to obtain hot-rolled wire rods, and the surface oxide scale is removed by hydrochloric acid pickling, and the temperature is raised to 900°C and kept for 2 hours, and then water-cooled, and the surface is cleaned by anhydrous ethanol, and then immersed in a composite lubricant, dried, and roughly cold drawn; Step 2: subjecting the hot-rolled wire rod obtained by rough drawing and cold drawing in step 1 to solution treatment and multi-stage aging treatment to obtain an iron-based high-temperature alloy wire; Step 3: The iron-based high-temperature alloy wire prepared in step 2 is subjected to surface pickling and copper plating, and fine drawing and cold drawing to obtain a surface-treated iron-based high-temperature alloy wire for cold heading.

[0005] Among them, the chemical composition of the iron-based high-temperature alloy is: in mass percentage, 0.04-0.08% C, 0.2-0.3% Si, 0.25-0.28% Mn, 0.05-0.10% Zr, 25-28% Ni, 12-14% Cr, 1.2-1.3% Mo, 1.7-2.0% Ti, 0.30-0.35% Al, 0.016-0.02% P, S≤0.005%, 0.2-0.3% V, 0.002-0.004% Y, 0.005-0.008% B, the balance is Fe and unavoidable impurities.

[0006] Step 1 The preparation steps of the composite lubricant are as follows: The fluorinated hexagonal boron nitride is ultrasonically dispersed in deionized water for 5-10 minutes and set aside; sodium carboxymethyl cellulose is ultrasonically dispersed in anhydrous ethanol for 3-5 minutes, and the dispersion is rapidly mixed with the fluorinated hexagonal boron nitride dispersion for 20-30 minutes, and polytetrafluoroethylene is added, and ultrasonic stirring is performed for 30 minutes, and magnesium oxide, polyacrylamide, ammonium dihydrogen phosphate, sodium ammonium hydrogen phosphate, and boric acid are added in sequence, and stirred for 1-2 hours; wherein the fluorinated hexagonal boron nitride is ultrasonically mixed with hexagonal boron nitride and ammonium fluoride in a mass ratio of 1: (1-3), and then magnetically stirred at 170-180° C. for 6 hours, and then ball milled at a speed of 300-350 r / min for 20-24 hours, and after the ball milling is completed, the ball milling is washed with deionized water and centrifugally dried; wherein the ball-to-material ratio is 1: (50-80).

[0007] In step 2, the solution treatment temperature is 980-1080°C, and the temperature is kept for 2 hours before oil cooling; the multi-stage aging treatment includes heating to 760-780°C, keeping for 8 hours, air cooling, and then heating to 650-680°C, keeping for 8 hours, and air cooling.

[0008] In step 3, the surface pickling and copper plating includes mixed acid pickling after shot blasting and then surface copper plating; wherein the mixed acid is nitric acid mixed with hydrofluoric acid, and the pickling speed is 2-3m / min.

[0009] The surface copper plating is specifically as follows: firstly, a plating aid treatment is performed for 2-3 minutes, and then a brass liquid is hot-dipped; wherein the temperature of the brass liquid is 980-1000°C, the hot-dip treatment is performed for 40-50 seconds, and the plating aid is taken out and air-cooled; wherein, the plating aid selected for the plating aid comprises: by weight, 5-10 parts of stannous chloride, 8-10 parts of ammonium chloride, 10-20 parts of potassium chloride, 50-70 parts of tetradecyl dimethyl benzyl ammonium chloride, 40-50 parts of alkylphenol polyoxyethylene ether, and 20-30 parts of anhydrous ethanol.

[0010] Compared with the prior art, the present invention has the following beneficial effects: 1. The wire rod prepared by the present invention is coated with a composite lubricant on the hot-rolled wire rod before rough drawing. The composite lubricant is added with hexagonal boron nitride and polytetrafluoroethylene for lubrication, which synergistically improves the anti-friction lubricating properties of the lubricant, reduces the wear of the wire rod in the rough drawing process as much as possible, is simpler and less polluting than the traditional phosphating and saponification process, and protects the alloy substrate at the same time.

[0011] 2. In the copper plating treatment before fine drawing and drawing of wire, hot-dip copper plating liquid is used. The process is simple and the copper plating layer is more uniform in thickness than the electroplated copper layer, with stable performance and less impurities. Before hot-dip copper, auxiliary plating treatment is performed to reduce the surface tension between the alloy matrix and the molten brass liquid, improve the wetting ability of the alloy matrix, and facilitate the formation of the immersion-plated layer. DETAILED DESCRIPTION

[0012] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making any creative work shall fall within the scope of protection of the present invention.

[0013] In the experiment, the chemical composition of the iron-based high-temperature alloy is: in mass percentage, 0.04% C, 0.3% Si, 0.26% Mn, 0.10% Zr, 28% Ni, 12% Cr, 1.2% Mo, 1.8% Ti, 0.35% Al, 0.016% P, 0.003% S, 0.2% V, 0.003% Y, 0.005% B, and the balance is Fe and unavoidable impurities.

[0014] The brass liquid is prepared by melting a cast brass ingot at 980°C, wherein the cast brass ingot is ZHD68, and the copper content is 67.0-70.0%; the particle size of hexagonal boron nitride is 1-2μm; the particle size of polytetrafluoroethylene is 5μm; the particle size of nano magnesium oxide is 50-100nm; and the average Mn of polyacrylamide is 150000.

[0015] Embodiment 1: This embodiment provides an iron-based high-temperature alloy wire for cold heading, comprising the following process steps: Step 1: The iron-based high-temperature alloy is smelted and hot-rolled to obtain hot-rolled wire rods. After being pickled with 10% hydrochloric acid to remove the surface oxide scale, the wire rods are heated to 900°C and kept for 2 hours, then water-cooled, and the surface is cleaned with anhydrous ethanol. The wire rods are then immersed in a composite lubricant, dried, and roughly cold-drawn. A total of 12 drawing passes are performed, and the surface reduction rate of each pass is about 15%; Step 2: subjecting the hot-rolled wire rod roughly drawn and cold-drawn in step 1 to solution treatment, heating to 980°C, keeping the temperature for 2 hours, and then oil cooling, performing multi-stage aging treatment, heating to 760°C, keeping the temperature for 8 hours, and then air cooling, and then heating to 650°C, keeping the temperature for 8 hours, and then air cooling, to obtain an iron-based high-temperature alloy wire; Step 3: The iron-based high-temperature alloy wire prepared in step 2 is subjected to surface pickling and copper plating, and is subjected to precision cold drawing, and the surface reduction rate is controlled to be about 3%, so as to obtain a surface-treated iron-based high-temperature alloy wire for cold heading.

[0016] Step 1 The preparation steps of the composite lubricant are as follows: Take 1 part of hexagonal boron nitride fluoride and put it in 100 parts of deionized water for ultrasonic dispersion for 10 minutes for standby use; put 0.1 part of sodium carboxymethyl cellulose in 10 parts of anhydrous ethanol for ultrasonic dispersion for 5 minutes, quickly mix with the above hexagonal boron nitride fluoride dispersion for ultrasonic 30 minutes, then add 10 parts of polytetrafluoroethylene, ultrasonically stir for 30 minutes, then add 0.4 parts of nano magnesium oxide, 0.5 parts of polyacrylamide, 4 parts of ammonium dihydrogen phosphate, 4 parts of sodium ammonium hydrogen phosphate, and 0.5 parts of boric acid in sequence, and stir for 1 hour; wherein, hexagonal boron nitride fluoride is ultrasonically mixed with hexagonal boron nitride and ammonium fluoride in a mass ratio of 1:2, and then magnetically stirred at 170°C for 6 hours, and then ball milled at a speed of 350r / min for 24 hours, washed with deionized water after ball milling, and centrifuged and dried; wherein the ball-to-material ratio is 1:60.

[0017] In step 3, the surface pickling and copper plating include mixed acid pickling after shot blasting and then surface copper plating; wherein the mixed acid is 100g / L nitric acid mixed with 30g / L hydrofluoric acid, and the pickling speed is 2m / min; the surface copper plating is specifically: firstly the auxiliary plating is treated at 70°C for 3min, and then hot-dip plating with brass solution; wherein the temperature of the brass solution is 980°C, hot-dip for 50s, and then taken out for air cooling; wherein, the auxiliary plating agent selected for auxiliary plating includes: by mass, 5 parts of stannous chloride, 10 parts of ammonium chloride, 10 parts of potassium chloride, 50 parts of tetradecyl dimethyl benzyl ammonium chloride, 40 parts of alkylphenol polyoxyethylene ether, and 30 parts of anhydrous ethanol. Embodiment 2: This embodiment provides an iron-based high-temperature alloy wire for cold heading, comprising the following process steps: Step 1: The iron-based high-temperature alloy is smelted and hot-rolled to obtain hot-rolled wire rods. After being pickled with 10% hydrochloric acid to remove the surface oxide scale, the wire rods are heated to 900°C and kept for 2 hours, then water-cooled, and the surface is cleaned with anhydrous ethanol. The wire rods are then immersed in a composite lubricant, dried, and roughly cold-drawn. A total of 12 drawing passes are performed, and the surface reduction rate of each pass is about 15%; Step 2: subjecting the hot-rolled wire rod roughly drawn and cold-drawn in step 1 to solution treatment, heating to 1000°C, keeping the temperature for 2 hours, and then oil cooling, performing multi-stage aging treatment, heating to 760°C, keeping the temperature for 8 hours, and then air cooling, and then heating to 680°C, keeping the temperature for 8 hours, and then air cooling, to obtain an iron-based high-temperature alloy wire; Step 3: The iron-based high-temperature alloy wire prepared in step 2 is subjected to surface pickling and copper plating, and is subjected to precision cold drawing, and the surface reduction rate is controlled to be about 3%, so as to obtain a surface-treated iron-based high-temperature alloy wire for cold heading.

[0018] Step 1 The preparation steps of the composite lubricant are as follows: Take 1 part of hexagonal boron nitride fluoride and put it in 100 parts of deionized water for ultrasonic dispersion for 10 minutes for standby use; put 0.1 part of sodium carboxymethyl cellulose in 10 parts of anhydrous ethanol for ultrasonic dispersion for 5 minutes, quickly mix with the above hexagonal boron nitride fluoride dispersion for ultrasonic 30 minutes, then add 10 parts of polytetrafluoroethylene, ultrasonically stir for 30 minutes, then add 0.4 parts of nano magnesium oxide, 0.5 parts of polyacrylamide, 4 parts of ammonium dihydrogen phosphate, 4 parts of sodium ammonium hydrogen phosphate, and 0.5 parts of boric acid in sequence, and stir for 1 hour; wherein, hexagonal boron nitride fluoride is ultrasonically mixed with hexagonal boron nitride and ammonium fluoride in a mass ratio of 1:2, and then magnetically stirred at 170°C for 6 hours, and then ball milled at a speed of 350r / min for 24 hours, washed with deionized water after ball milling, and centrifuged and dried; wherein the ball-to-material ratio is 1:60.

[0019] In step 3, the surface pickling and copper plating include mixed acid pickling after shot blasting and then surface copper plating; wherein the mixed acid is 100g / L nitric acid mixed with 30g / L hydrofluoric acid, and the pickling speed is 2m / min; the surface copper plating is specifically: firstly the auxiliary plating is treated at 70°C for 3min, and then hot-dip plating with brass solution; wherein the temperature of the brass solution is 980°C, hot-dip for 50s, and air-cooled, wherein the auxiliary plating agent selected for auxiliary plating includes: by mass, 6 parts of stannous chloride, 10 parts of ammonium chloride, 10 parts of potassium chloride, 50 parts of tetradecyl dimethyl benzyl ammonium chloride, 50 parts of alkylphenol polyoxyethylene ether, and 30 parts of anhydrous ethanol. Embodiment 3: This embodiment provides an iron-based high-temperature alloy wire for cold heading, comprising the following process steps: Step 1: The iron-based high-temperature alloy is smelted and hot-rolled to obtain hot-rolled wire rods. After being pickled with 10% hydrochloric acid to remove the surface oxide scale, the wire rods are heated to 900°C and kept for 2 hours, then water-cooled, and the surface is cleaned with anhydrous ethanol. The wire rods are then immersed in a composite lubricant, dried, and roughly cold-drawn. A total of 12 drawing passes are performed, and the surface reduction rate of each pass is about 15%; Step 2: subjecting the hot-rolled wire rod roughly drawn and cold-drawn in step 1 to solution treatment, heating to 1020°C, keeping warm for 2 hours, and then oil cooling, performing multi-stage aging treatment, heating to 780°C, keeping warm for 8 hours, and then air cooling, and then heating to 680°C, keeping warm for 8 hours, and then air cooling, to obtain an iron-based high-temperature alloy wire; Step 3: The iron-based high-temperature alloy wire prepared in step 2 is subjected to surface pickling and copper plating, and is subjected to precision cold drawing, and the surface reduction rate is controlled to be about 3%, so as to obtain a surface-treated iron-based high-temperature alloy wire for cold heading.

[0020] Step 1 The preparation steps of the composite lubricant are as follows: Take 1 part of hexagonal boron nitride fluoride and put it in 100 parts of deionized water for ultrasonic dispersion for 10 minutes for standby use; put 0.1 part of sodium carboxymethyl cellulose in 10 parts of anhydrous ethanol for ultrasonic dispersion for 5 minutes, quickly mix with the above hexagonal boron nitride fluoride dispersion for ultrasonic 30 minutes, then add 10 parts of polytetrafluoroethylene, ultrasonically stir for 30 minutes, then add 0.4 parts of nano magnesium oxide, 0.5 parts of polyacrylamide, 4 parts of ammonium dihydrogen phosphate, 4 parts of sodium ammonium hydrogen phosphate, and 0.5 parts of boric acid in sequence, and stir for 1 hour; wherein, hexagonal boron nitride fluoride is ultrasonically mixed with hexagonal boron nitride and ammonium fluoride in a mass ratio of 1:2, and then magnetically stirred at 170°C for 6 hours, and then ball milled at a speed of 350r / min for 24 hours, washed with deionized water after ball milling, and centrifuged and dried; wherein the ball-to-material ratio is 1:60.

[0021] In step 3, the surface pickling and copper plating include mixed acid pickling after shot blasting and then surface copper plating; wherein the mixed acid is 100g / L nitric acid mixed with 30g / L hydrofluoric acid, and the pickling speed is 3m / min; the surface copper plating is specifically: first the auxiliary plating is treated at 70°C for 3min, and then hot-dip plating with brass solution; wherein the temperature of the brass solution is 980°C, hot-dip 50s, and air-cooled; wherein the auxiliary plating agent selected for auxiliary plating includes: by mass, 10 parts of stannous chloride, 10 parts of ammonium chloride, 20 parts of potassium chloride, 60 parts of tetradecyl dimethyl benzyl ammonium chloride, 50 parts of alkylphenol polyoxyethylene ether, and 30 parts of anhydrous ethanol. Embodiment 4: This embodiment provides an iron-based high-temperature alloy wire for cold heading, comprising the following process steps: Step 1: The iron-based high-temperature alloy is smelted and hot-rolled to obtain hot-rolled wire rods. After being pickled with 10% hydrochloric acid to remove the surface oxide scale, the wire rods are heated to 900°C and kept for 2 hours, then water-cooled, and the surface is cleaned with anhydrous ethanol. The wire rods are then immersed in a composite lubricant, dried, and roughly cold-drawn. A total of 12 drawing passes are performed, and the surface reduction rate of each pass is about 15%; Step 2: subjecting the hot-rolled wire rod roughly drawn and cold-drawn in step 1 to solution treatment, heating to 1040°C, keeping the temperature for 2 hours, and then oil cooling, performing multi-stage aging treatment, heating to 780°C, keeping the temperature for 8 hours, and then air cooling, and then heating to 650°C, keeping the temperature for 8 hours, and then air cooling, to obtain an iron-based high-temperature alloy wire; Step 3: The iron-based high-temperature alloy wire prepared in step 2 is subjected to surface pickling and copper plating, and is subjected to precision cold drawing, and the surface reduction rate is controlled to be about 3%, so as to obtain a surface-treated iron-based high-temperature alloy wire for cold heading.

[0022] Step 1 The preparation steps of the composite lubricant are as follows: Take 1 part of hexagonal boron nitride fluoride and put it in 100 parts of deionized water for ultrasonic dispersion for 10 minutes for standby use; put 0.1 part of sodium carboxymethyl cellulose in 10 parts of anhydrous ethanol for ultrasonic dispersion for 5 minutes, quickly mix with the above hexagonal boron nitride fluoride dispersion for ultrasonic 30 minutes, then add 10 parts of polytetrafluoroethylene, ultrasonically stir for 30 minutes, then add 0.4 parts of nano magnesium oxide, 0.5 parts of polyacrylamide, 4 parts of ammonium dihydrogen phosphate, 4 parts of sodium ammonium hydrogen phosphate, and 0.5 parts of boric acid in sequence, and stir for 1 hour; wherein, hexagonal boron nitride fluoride is ultrasonically mixed with hexagonal boron nitride and ammonium fluoride in a mass ratio of 1:2, and then magnetically stirred at 170°C for 6 hours, and then ball milled at a speed of 350r / min for 24 hours, washed with deionized water after ball milling, and centrifuged and dried; wherein the ball-to-material ratio is 1:60.

[0023] In step 3, the surface pickling and copper plating include mixed acid pickling after shot blasting and then surface copper plating; wherein the mixed acid is 100g / L nitric acid mixed with 30g / L hydrofluoric acid, and the pickling speed is 3m / min; the surface copper plating is specifically: first the auxiliary plating is treated at 70°C for 3min, and then hot-dip plating with brass solution; wherein the temperature of the brass solution is 980°C, hot-dip 50s, and air-cooled; wherein the auxiliary plating agent selected for auxiliary plating includes: by mass, 10 parts of stannous chloride, 10 parts of ammonium chloride, 20 parts of potassium chloride, 60 parts of tetradecyl dimethyl benzyl ammonium chloride, 40 parts of alkylphenol polyoxyethylene ether, and 30 parts of anhydrous ethanol. Embodiment 5: This embodiment provides an iron-based high-temperature alloy wire for cold heading, comprising the following process steps: Step 1: The iron-based high-temperature alloy is smelted and hot-rolled to obtain hot-rolled wire rods. After being pickled with 10% hydrochloric acid to remove the surface oxide scale, the wire rods are heated to 900°C and kept for 2 hours, then water-cooled, and the surface is cleaned with anhydrous ethanol. The wire rods are then immersed in a composite lubricant, dried, and roughly cold-drawn. A total of 12 drawing passes are performed, and the surface reduction rate of each pass is about 15%; Step 2: subjecting the hot-rolled wire rod roughly drawn and cold-drawn in step 1 to a solution treatment, heating to 1060°C, keeping the temperature for 2 hours, and then oil cooling, performing a multi-stage aging treatment, heating to 780°C, keeping the temperature for 8 hours, and then air cooling, and then heating to 680°C, keeping the temperature for 8 hours, and then air cooling, to obtain an iron-based high-temperature alloy wire; Step 3: The iron-based high-temperature alloy wire prepared in step 2 is subjected to surface pickling and copper plating, and is subjected to precision cold drawing, and the surface reduction rate is controlled to be about 3%, so as to obtain a surface-treated iron-based high-temperature alloy wire for cold heading.

[0024] Step 1 The preparation steps of the composite lubricant are as follows: Take 1 part of hexagonal boron nitride fluoride and put it in 100 parts of deionized water for ultrasonic dispersion for 10 minutes for standby use; put 0.1 part of sodium carboxymethyl cellulose in 10 parts of anhydrous ethanol for ultrasonic dispersion for 5 minutes, quickly mix with the above hexagonal boron nitride fluoride dispersion for ultrasonic 30 minutes, then add 10 parts of polytetrafluoroethylene, ultrasonic stirring for 30 minutes, then add 0.4 parts of nano magnesium oxide, 0.5 parts of polyacrylamide, 4 parts of ammonium dihydrogen phosphate, 4 parts of sodium ammonium hydrogen phosphate, and 0.5 parts of boric acid in sequence, and stir for 1 hour; wherein, hexagonal boron nitride fluoride is ultrasonically mixed with hexagonal boron nitride and ammonium fluoride in a mass ratio of 1:1, and then magnetically stirred at 170°C for 6 hours, and then ball milled at a speed of 350r / min for 24 hours, washed with deionized water after ball milling and centrifugal dried; wherein the ball-to-material ratio is 1:60.

[0025] In step 3, the surface pickling and copper plating include mixed acid pickling after shot blasting and then surface copper plating; wherein the mixed acid is 100g / L nitric acid mixed with 30g / L hydrofluoric acid, and the pickling speed is 3m / min; the surface copper plating is specifically: first the auxiliary plating is treated at 70°C for 3min, and then hot-dip plating with brass solution; wherein the temperature of the brass solution is 980°C, hot-dip 50s, and air-cooled; wherein the auxiliary plating agent selected for auxiliary plating includes: by mass, 10 parts of stannous chloride, 10 parts of ammonium chloride, 20 parts of potassium chloride, 60 parts of tetradecyl dimethyl benzyl ammonium chloride, 40 parts of alkylphenol polyoxyethylene ether, and 30 parts of anhydrous ethanol. Embodiment 6: This embodiment provides an iron-based high-temperature alloy wire for cold heading, comprising the following process steps: Step 1: The iron-based high-temperature alloy is smelted and hot-rolled to obtain hot-rolled wire rods. After being pickled with 10% hydrochloric acid to remove the surface oxide scale, the wire rods are heated to 900°C and kept for 2 hours, then water-cooled, and the surface is cleaned with anhydrous ethanol. The wire rods are then immersed in a composite lubricant, dried, and roughly cold-drawn. A total of 12 drawing passes are performed, and the surface reduction rate of each pass is about 15%; Step 2: subjecting the hot-rolled wire rod roughly drawn and cold-drawn in step 1 to solid solution treatment, heating to 1080°C, keeping warm for 2 hours and then oil cooling, performing multi-stage aging treatment, heating to 780°C, keeping warm for 8 hours and then air cooling, and then heating to 680°C, keeping warm for 8 hours and then air cooling, to obtain an iron-based high-temperature alloy wire; Step 3: The iron-based high-temperature alloy wire prepared in step 2 is subjected to surface pickling and copper plating, and is subjected to precision cold drawing, and the surface reduction rate is controlled to be about 3%, so as to obtain a surface-treated iron-based high-temperature alloy wire for cold heading.

[0026] Step 1 The preparation steps of the composite lubricant are as follows: Take 1 part of hexagonal boron nitride fluoride and put it in 100 parts of deionized water for ultrasonic dispersion for 10 minutes for standby use; put 0.1 part of sodium carboxymethyl cellulose in 10 parts of anhydrous ethanol for ultrasonic dispersion for 5 minutes, quickly mix with the above hexagonal boron nitride fluoride dispersion for ultrasonic 30 minutes, then add 10 parts of polytetrafluoroethylene, ultrasonic stirring for 30 minutes, then add 0.4 parts of nano magnesium oxide, 0.5 parts of polyacrylamide, 4 parts of ammonium dihydrogen phosphate, 4 parts of sodium ammonium hydrogen phosphate, and 0.5 parts of boric acid in sequence, and stir for 1 hour; wherein, hexagonal boron nitride fluoride is ultrasonically mixed with hexagonal boron nitride and ammonium fluoride in a mass ratio of 1:1, and then magnetically stirred at 170°C for 6 hours, and then ball milled at a speed of 350r / min for 24 hours, washed with deionized water after ball milling and centrifugal dried; wherein the ball-to-material ratio is 1:60.

[0027] In step 3, the surface pickling and copper plating include mixed acid pickling after shot blasting and then surface copper plating; wherein the mixed acid is 100g / L nitric acid mixed with 30g / L hydrofluoric acid, and the pickling speed is 3m / min; the surface copper plating is specifically: first the auxiliary plating is treated at 70°C for 3min, and then hot-dip plating with brass solution; wherein the temperature of the brass solution is 980°C, hot-dip 50s, and air-cooled; wherein the auxiliary plating agent selected for auxiliary plating includes: by mass, 10 parts of stannous chloride, 10 parts of ammonium chloride, 20 parts of potassium chloride, 70 parts of tetradecyl dimethyl benzyl ammonium chloride, 40 parts of alkylphenol polyoxyethylene ether, and 30 parts of anhydrous ethanol. Embodiment 7: This embodiment provides an iron-based high-temperature alloy wire for cold heading, comprising the following process steps: Step 1: The iron-based high-temperature alloy is smelted and hot-rolled to obtain hot-rolled wire rods. After being pickled with 10% hydrochloric acid to remove the surface oxide scale, the wire rods are heated to 900°C and kept for 2 hours, then water-cooled, and the surface is cleaned with anhydrous ethanol. The wire rods are then immersed in a composite lubricant, dried, and roughly cold-drawn. A total of 12 drawing passes are performed, and the surface reduction rate of each pass is about 15%; Step 2: subjecting the hot-rolled wire rod roughly drawn and cold-drawn in step 1 to solid solution treatment, heating to 1080°C, keeping warm for 2 hours and then oil cooling, performing multi-stage aging treatment, heating to 780°C, keeping warm for 8 hours and then air cooling, and then heating to 680°C, keeping warm for 8 hours and then air cooling, to obtain an iron-based high-temperature alloy wire; Step 3: The iron-based high-temperature alloy wire prepared in step 2 is subjected to surface pickling and copper plating, and is subjected to precision cold drawing, and the surface reduction rate is controlled to be about 3%, so as to obtain a surface-treated iron-based high-temperature alloy wire for cold heading.

[0028] Step 1 The preparation steps of the composite lubricant are as follows: Take 1 part of hexagonal boron nitride fluoride and put it in 100 parts of deionized water for ultrasonic dispersion for 10 minutes for standby use; put 0.1 part of sodium carboxymethyl cellulose in 10 parts of anhydrous ethanol for ultrasonic dispersion for 5 minutes, quickly mix with the above hexagonal boron nitride fluoride dispersion for ultrasonic 30 minutes, then add 10 parts of polytetrafluoroethylene, ultrasonically stir for 30 minutes, then add 0.4 parts of nano magnesium oxide, 0.5 parts of polyacrylamide, 4 parts of ammonium dihydrogen phosphate, 4 parts of sodium ammonium hydrogen phosphate, and 0.5 parts of boric acid in sequence, and stir for 1 hour; wherein, hexagonal boron nitride fluoride is ultrasonically mixed with hexagonal boron nitride and ammonium fluoride in a mass ratio of 1:2, and then magnetically stirred at 170°C for 6 hours, and then ball milled at a speed of 350r / min for 24 hours, washed with deionized water after ball milling, and centrifuged and dried; wherein the ball-to-material ratio is 1:50.

[0029] In step 3, the surface pickling and copper plating include mixed acid pickling after shot blasting and then surface copper plating; wherein the mixed acid is 100g / L nitric acid mixed with 30g / L hydrofluoric acid, and the pickling speed is 3m / min; the surface copper plating is specifically: first the auxiliary plating is treated at 70°C for 3min, and then hot-dip plating with brass solution; wherein the temperature of the brass solution is 980°C, hot-dip 50s, and air-cooled; wherein the auxiliary plating agent selected for auxiliary plating includes: by mass, 10 parts of stannous chloride, 10 parts of ammonium chloride, 20 parts of potassium chloride, 50 parts of tetradecyl dimethyl benzyl ammonium chloride, 40 parts of alkylphenol polyoxyethylene ether, and 30 parts of anhydrous ethanol. Detection test The cold-forging iron-based high-temperature alloy wires of Examples 1-7 were used to cold-forge fasteners, and high-temperature tensile tests were performed according to GB / T 228.2. The tensile strength and yield strength were tested at a test temperature of 650°C. The data are as follows:

[0030] Conclusion: The wire produced by the present invention is suitable for cold heading processing, and the cold heading fasteners produced can be used in a high temperature working environment of 650°C.

[0031] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A surface treatment process for iron-based high-temperature alloy wire for cold heading, characterized in that: The process steps include: Step 1: The iron-based high-temperature alloy is smelted and hot-rolled to obtain hot-rolled wire rods, and the surface oxide scale is removed by hydrochloric acid pickling, and the temperature is raised to 900°C and kept for 2 hours, and then water-cooled, and the surface is cleaned by anhydrous ethanol, and then immersed in a composite lubricant, dried, and roughly cold drawn; Step 2: subjecting the hot-rolled wire rod obtained by rough drawing and cold drawing in step 1 to solution treatment and multi-stage aging treatment to obtain an iron-based high-temperature alloy wire; Step 3: The iron-based high-temperature alloy wire prepared in step 2 is subjected to surface pickling and copper plating, and fine drawing and cold drawing to obtain a surface-treated iron-based high-temperature alloy wire for cold heading.

2. The surface treatment process of a cold heading iron-based high-temperature alloy wire according to claim 1, characterized in that: The chemical composition of the iron-based high-temperature alloy is: in mass percentage, 0.04-0.08% C, 0.2-0.3% Si, 0.25-0.28% Mn, 0.05-0.10% Zr, 25-28% Ni, 12-14% Cr, 1.2-1.3% Mo, 1.7-2.0% Ti, 0.30-0.35% Al, 0.016-0.02% P, S≤0.005%, 0.2-0.3% V, 0.002-0.004% Y, 0.005-0.008% B, the balance is Fe and unavoidable impurities.

3. The surface treatment process of a cold heading iron-based high temperature alloy wire according to claim 1, characterized in that: Step 1 The preparation steps of the composite lubricant are as follows: Place hexagonal boron nitride fluoride in deionized water and ultrasonically disperse for 5-10 minutes for use; place sodium carboxymethyl cellulose in anhydrous ethanol and ultrasonically disperse for 3-5 minutes, quickly mix with the above hexagonal boron nitride fluoride dispersion for 20-30 minutes, then add polytetrafluoroethylene, ultrasonically stir for 30 minutes, then add magnesium oxide, polyacrylamide, ammonium dihydrogen phosphate, sodium ammonium hydrogen phosphate, and boric acid in sequence, and stir for 1-2 hours.

4. The surface treatment process of a cold heading iron-based high-temperature alloy wire according to claim 3, characterized in that: The fluorinated hexagonal boron nitride is prepared by ultrasonically mixing hexagonal boron nitride and ammonium fluoride in a mass ratio of 1:(1-3), magnetically stirring at 170-180°C for 6 hours, and then ball milling at a speed of 300-350 r / min for 20-24 hours. After the ball milling, the mixture is washed with deionized water and centrifugally dried.

5. The surface treatment process of a cold heading iron-based high temperature alloy wire according to claim 1, characterized in that: In step 2, the solution treatment temperature is 980-1080°C, and the temperature is kept for 2 hours before oil cooling; the multi-stage aging treatment includes heating to 760-780°C, keeping for 8 hours, air cooling, and then heating to 650-680°C, keeping for 8 hours, and air cooling.

6. The surface treatment process of a cold heading iron-based high temperature alloy wire according to claim 1, characterized in that: In step 3, the surface pickling and copper plating includes mixed acid pickling after shot blasting and then surface copper plating; wherein the mixed acid is nitric acid mixed with hydrofluoric acid, and the pickling speed is 2-3m / min.

7. The surface treatment process of the iron-based high-temperature alloy wire for cold heading according to claim 5, characterized in that: The surface copper plating is specifically as follows: firstly, the copper plating treatment is carried out for 2-3 minutes, and then, the copper plating is carried out by hot dipping in a brass liquid; wherein the temperature of the brass liquid is 980-1000°C, the copper plating is carried out by hot dipping for 40-50 seconds, and the copper plating is carried out by air cooling.

8. The surface treatment process of the iron-based high-temperature alloy wire for cold heading according to claim 6, characterized in that: The plating aid selected for plating includes: by weight, 5-10 parts of stannous chloride, 8-10 parts of ammonium chloride, 10-20 parts of potassium chloride, 50-70 parts of tetradecyl dimethyl benzyl ammonium chloride, 40-50 parts of alkylphenol polyoxyethylene ether, and 20-30 parts of anhydrous ethanol.

9. The surface treatment process of a cold heading iron-based high temperature alloy wire according to claim 1, characterized in that: In the rough cold drawing, 12 drawing passes are carried out, and the surface reduction rate of each pass is 10-20%; in the fine cold drawing, the surface reduction rate is controlled at 2-5%.

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