High-temperature-resistant alloy for automobile engine and preparation process of high-temperature-resistant alloy

Abstract

The invention discloses a high-temperature-resistant alloy for an automobile engine and a preparation process of the high-temperature-resistant alloy, and relates to the technical field of alloy materials. The high-temperature-resistant alloy comprises the following chemical components in percentage by mass: 0.03%-0.08% of C, less than or equal to 1.00% of Si, less than or equal to 2.00% of Mn, 13.5%-16.0% of Cr, 24.00%-27.00% of Ni, 1.90%-2.35% of Ti, less than or equal to 0.350% of Al, 1.00%-1.50% of Mo, 0.10%-0.50% of V, 0.003%-0.010% of B, less than or equal to 0.015% of P, less than or equal to 0.001% of S and the balance of Fe and inevitable impurity components. The high-temperature-resistant, friction-resistant and wear-resistant alloy is applied to the surface of matrix steel for laser cladding, then a layer of nickel-based alloy is cladded, and the high-temperature-resistant, friction-resistant and wear-resistant performance is good.

Description

Technical Field

[0001] The invention relates to the technical field of alloy materials, in particular to a high temperature resistant alloy for automobile engines and a preparation process thereof. Background Art

[0002] In recent years, the state has always required the automobile industry to implement energy conservation and emission reduction. At present, the energy conservation and emission reduction measures of automobile enterprises mainly include lightweighting of the whole vehicle and the use of high-efficiency internal combustion engines, turbocharging technology, automatic transmission, hybrid power, electronic control technology, etc. Among them, turbocharging technology can improve the engine's specific power and specific torque and realize engine miniaturization, so it is considered to be a more economical and effective energy conservation and emission reduction technology. However, due to the high speed of the turbocharger and the service temperature of up to 1000℃, heat-resistant materials must be used, and the most critical parts are fasteners. Because A286 alloy has good thermal stability, plasticity and good corrosion resistance, it is currently the largest fastener material used in automobile engines. It is mainly used as a connector between the supercharger and the exhaust manifold / catalyst, the exhaust manifold and the cylinder head, and the catalyst and the exhaust pipe. The number of pieces used generally ranges from 3 to 9.

[0003] A286 series high temperature alloys are equivalent to our domestic GH2132 alloys. Our domestic GH2132 alloys are mainly used in the manufacture of high temperature fasteners for military applications. To transform them into civilian products, they need to be optimized in terms of cost and price, otherwise they will not be competitive in the market. Summary of the invention

[0004] The object of the present invention is to provide a high temperature resistant alloy for automobile engines and a preparation process thereof, so as to solve the problems raised in the prior art.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A high temperature resistant alloy for automobile engines, the chemical components of which are as follows by mass percentage: C: 0.03-0.08%, Si≤1.00%, Mn≤2.00%, Cr: 13.5-16.0%, Ni: 24.00-27.00%, Ti: 1.90-2.35%, Al≤0.350%, Mo: 1.00-1.50%, V: 0.10-0.50%, B: 0.003-0.010%, P≤0.015%, S≤0.001%, and the rest are Fe and unavoidable impurity components.

[0007] Preferably, the chemical components of the high temperature resistant alloy include, by mass percentage: C: 0.03-0.08%, Si≤0.30%, Mn≤1.00%, Cr: 13.5-16.0%, Ni: 24.00-25.00%, Ti: 1.90-2.35%, Al: 0.10-3.00%, Mo: 1.00-1.20%, V: 0.10-0.20%, B: 0.003-0.006%, P≤0.015%, S≤0.001%, Y+Ce≤0.30%, and the rest are Fe and unavoidable impurity components.

[0008] The specific preparation process of the above high temperature resistant alloy is: adopt EAF+ESR double smelting process, put the alloy raw materials and pre-desulfurized scrap steel into an electric arc furnace, smelt by electricity, cast the electrode rod after slag removal, transfer to the electroslag furnace for remelting, and get the electroslag ingot after homogenization annealing, forge and roll to form square billets, descale and peel to roll wire rods, and pickle after solution annealing; the specifications of the electrode rod are: Specifications of electroslag ingots

[0009] Preferably, the steel-out temperature of the electric arc furnace is 1650-1675°C; the slag added to the electric slag furnace includes the following raw materials by mass percentage: CaF2: 50-70%, Al2O3: 10-20%, CaO: 0-10%, TiO2: 8-10%; the melting rate is 8-10kg / min.

[0010] Preferably, the temperature of homogenization annealing is 1225-1275° C., and the temperature is kept for 6-8 hours; the temperature of solution annealing is 950-1000° C., and the temperature is kept for 1 hour and then water-cooled.

[0011] An application of a high temperature resistant alloy for an engine comprises the following steps:

[0012] 1) Pre-treat the surface of the base steel by sanding it with sandpaper and then cleaning and drying it with acetone;

[0013] 2) taking a high temperature resistant alloy, laser cladding the surface of the pretreated base steel to form an iron-based cladding layer, and then performing heat treatment;

[0014] 3) Taking nickel-based high-temperature alloy powder, laser powder feeding is used for cladding to form a nickel-based cladding layer on the surface of the iron-based cladding layer, and aging treatment is performed to obtain a finished product.

[0015] Preferably, the process parameters of laser cladding of high temperature resistant alloy are: argon flow rate is 20L / min-30L / min, laser power is 1500W-1800W, spot diameter is 5mm, and cladding scanning speed is 4mm / s-6mm / s.

[0016] The process parameters of laser powder cladding are: coaxial powder feeding, argon gas flow rate of 20L / min-30L / min, laser power of 2000W~2400W; spot diameter of 5mm; defocus of laser cladding head is +15mm~+30mm, powder feeding speed is 200mg / s~300mg / s, and cladding scanning speed is 4mm / s~6mm / s.

[0017] Preferably, the thickness of the iron-based cladding layer is 2 mm; the thickness of the nickel-based cladding layer is 1 mm; the heat treatment process parameters are: solution treatment at 950-980°C for 1-2 hours and then air cooling; the aging treatment process parameters are: aging treatment at 720-750°C for 8-10 hours, then cooling to 600-620°C for 8-10 hours, and finally air cooling to room temperature.

[0018] Preferably, the chemical components of the base steel include, by mass percentage: C≤0.03%, Mn≤2.00%, Cr:16-18%, Ni:10-14%, Mo:2.00-3.00%, and the rest are Fe and unavoidable impurity components;

[0019] The chemical components of the nickel-based high-temperature alloy powder include, by mass percentage: C: 0.03-0.04%, Cr: 17-21%, Ni: 50.00-55.00%, Ti: 0.65-1.15%, Al: 0.2-0.8%, Nb+Ta: 4.75-5.5%, Mo: 2.8-3.3%, and the rest are Fe and unavoidable impurity components.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. The present invention improves the overall high-temperature resistance by cladding two layers of high-temperature alloy on the surface of the base steel, wherein the iron-based alloy layer is laser-clad on the surface of the base steel by independently produced high-temperature resistant alloy; it can be seen from the composition of the base steel, iron-based alloy and nickel-based alloy that the Ni content presents a gradient change, and the iron-based alloy is used as a transition layer to improve the interface bonding strength between the base steel and the nickel-based alloy. At the same time, the gradient structure can disperse the thermal load, avoid local stress concentration, and synergistically improve the comprehensive performance and service life of the alloy.

[0022] 2. From the perspective of economy, the purpose of the present invention is to optimize the cost price of alloy materials and improve market competitiveness. Therefore, the iron-based alloy wire rod is optimized and designed based on the A286 synthetic composition, and the components of some expensive elements such as Ni and Mo are reduced as much as possible to reduce costs, but at the same time, the component of the Al element is increased to increase the precipitation of Ni3(Al,Ti)γ′ and γ phases in the alloy material, and the Al and Ti contents are controlled to reduce the precipitation of Ni2AlTi harmful phases as much as possible; in addition, the introduction of rare earth elements Y and Ce inhibits the formation of TCP phase by changing the segregation of alloy elements, reduces the generation of cracks, and improves the production quality of wire rods; in the smelting and remelting process, the present invention does not perform smelting steps such as refining, allowing impurity elements to be within a certain range, reducing processing costs, and can be used in the civilian industry; in the preparation of alloy materials, iron-based alloys and nickel-based alloys are used as cladding layers to be clad on the surface of the base steel. The cost price of the base steel is much lower than the above-mentioned high-temperature alloy, but the synthesized alloy material can also adapt well to high-temperature operations. DETAILED DESCRIPTION

[0023] 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.

[0024] In the experiment, a 4K fiber laser was used for laser cladding;

[0025] The slag added to the electroslag furnace includes the following raw materials by mass percentage: CaF2: 70%, Al2O3: 15%, CaO: 5%, TiO2: 10%;

[0026] The chemical components of the base steel include, by mass percentage, C: 0.02%, Mn: 2.00%, Cr: 17.14%, Ni: 12.54%, Mo: 2.12%, and the rest are Fe and unavoidable impurity components;

[0027] The chemical components of the nickel-based high-temperature alloy powder include, by mass percentage: C: 0.04%, Cr: 19.17%, Ni: 52.41%, Ti: 0.94%, Al: 0.43%, Nb: 5.19%, Ta: 0.21%, Mo: 3.19%, and the rest are Fe and unavoidable impurity components;

[0028] Embodiment 1: This embodiment provides a high temperature resistant alloy for automobile engines, which specifically includes the following steps:

[0029] The EAF+ESR dual smelting process is adopted. The alloy raw materials and pre-desulfurized scrap steel are placed in an electric arc furnace, and smelted by electricity. After steel is tapped and slag is removed, electrode rods are cast to obtain electrode rods, which are then transferred to an electroslag furnace, and slag is added and remelted to obtain electroslag ingots. After homogenization annealing, the billets are forged and rolled to form square billets, and the wire rods are rolled after descaling and peeling treatment. The high-temperature resistant alloy is obtained by pickling.

[0030] Among them, the tapping temperature of the electric arc furnace is 1675℃; the melting rate in the electric slag furnace is 8kg / min;

[0031] The homogenization annealing temperature is 1250°C, and after keeping the temperature for 8 hours, the quenching is performed to room temperature;

[0032] The solution annealing temperature is 980℃, which is kept for 1h and then water-cooled;

[0033] The chemical composition of the high temperature resistant alloy is as follows: C: 0.040%, Si: 0.26%, Mn: 0.59%, Cr: 14.04%, Ni: 24.75%, Ti: 2.18%, Al: 0.15%, Mo: 1.19%, V: 0.15%, B: 0.006%, P: 0.013%, S: 0.001%, and the rest is Fe and unavoidable impurity components.

[0034] Embodiment 2: This embodiment provides a high temperature resistant alloy for automobile engines, which specifically includes the following steps:

[0035] The EAF+ESR dual smelting process is adopted. The alloy raw materials and pre-desulfurized scrap steel are placed in an electric arc furnace, and smelted by electricity. After steel is tapped and slag is removed, electrode rods are cast to obtain electrode rods, which are then transferred to an electroslag furnace, and slag is added and remelted to obtain electroslag ingots. After homogenization annealing, the billets are forged and rolled to form square billets, and the wire rods are rolled after descaling and peeling treatment. The high-temperature resistant alloy is obtained by pickling.

[0036] Among them, the tapping temperature of the electric arc furnace is 1675℃; the melting rate in the electric slag furnace is 8kg / min;

[0037] The homogenization annealing temperature is 1250°C, and after keeping the temperature for 8 hours, the quenching is performed to room temperature;

[0038] The solution annealing temperature is 980℃, which is kept for 1h and then water-cooled;

[0039] The chemical composition of the high temperature resistant alloy is as follows: C: 0.050%, Si: 0.07%, Mn: 0.64%, Cr: 14.05%, Ni: 24.73%, Ti: 2.12%, Al: 0.16%, Mo: 1.17%, V: 0.12%, B: 0.005%, P: 0.012%, S: 0.001%, and the rest is Fe and unavoidable impurity components.

[0040] Embodiment 3: This embodiment provides a high temperature resistant alloy for automobile engines, which specifically includes the following steps:

[0041] The EAF+ESR dual smelting process is adopted. The alloy raw materials and pre-desulfurized scrap steel are placed in an electric arc furnace, and smelted by electricity. After steel is tapped and slag is removed, electrode rods are cast to obtain electrode rods, which are then transferred to an electroslag furnace, and slag is added and remelted to obtain electroslag ingots. After homogenization annealing, the billets are forged and rolled to form square billets, and the wire rods are rolled after descaling and peeling treatment. The high-temperature resistant alloy is obtained by pickling.

[0042] Among them, the tapping temperature of the electric arc furnace is 1675℃; the melting rate in the electric slag furnace is 8kg / min;

[0043] The homogenization annealing temperature is 1250°C, and after keeping the temperature for 8 hours, the quenching is performed to room temperature;

[0044] The solution annealing temperature is 980℃, which is kept for 1h and then water-cooled;

[0045] The chemical composition of the high temperature resistant alloy is as follows: C: 0.050%, Si: 0.07%, Mn: 0.66%, Cr: 13.92%, Ni: 24.71%, Ti: 2.12%, Al: 0.14%, Mo: 1.15%, V: 0.11%, B: 0.005%, P: 0.014%, S: 0.001%, and the rest is Fe and unavoidable impurity components.

[0046] Embodiment 4: This embodiment provides a high temperature resistant alloy for automobile engines, which specifically includes the following steps:

[0047] The EAF+ESR dual smelting process is adopted. The alloy raw materials and pre-desulfurized scrap steel are placed in an electric arc furnace, and smelted by electricity. After steel is tapped and slag is removed, electrode rods are cast to obtain electrode rods, which are then transferred to an electroslag furnace, and slag is added and remelted to obtain electroslag ingots. After homogenization annealing, the billets are forged and rolled to form square billets, and the wire rods are rolled after descaling and peeling treatment. The high-temperature resistant alloy is obtained by pickling.

[0048] Among them, the tapping temperature of the electric arc furnace is 1675℃; the melting rate in the electric slag furnace is 8kg / min;

[0049] The homogenization annealing temperature is 1250°C, and after keeping the temperature for 8 hours, the quenching is performed to room temperature;

[0050] The solution annealing temperature is 980℃, which is kept for 1h and then water-cooled;

[0051] The chemical composition of the high temperature resistant alloy is as follows: C: 0.040%, Si: 0.13%, Mn: 1.35%, Cr: 14.01%, Ni: 24.60%, Ti: 2.15%, Al: 0.15%, Mo: 1.15%, V: 0.15%, B: 0.004%, P: 0.015%, S: 0.001%, and the rest is Fe and unavoidable impurity components.

[0052] Embodiment 5: This embodiment provides a high temperature resistant alloy for automobile engines, which specifically includes the following steps:

[0053] The EAF+ESR dual smelting process is adopted. The alloy raw materials and pre-desulfurized scrap steel are placed in an electric arc furnace, and smelted by electricity. After steel is tapped and slag is removed, electrode rods are cast to obtain electrode rods, which are then transferred to an electroslag furnace, and slag is added and remelted to obtain electroslag ingots. After homogenization annealing, the billets are forged and rolled to form square billets, and the wire rods are rolled after descaling and peeling treatment. The high-temperature resistant alloy is obtained by pickling.

[0054] Among them, the tapping temperature of the electric arc furnace is 1675℃; the melting rate in the electric slag furnace is 8kg / min;

[0055] The homogenization annealing temperature is 1250°C, and after keeping the temperature for 8 hours, the quenching is performed to room temperature;

[0056] The solution annealing temperature is 980℃, which is kept for 1h and then water-cooled;

[0057] The chemical composition of the high temperature resistant alloy is as follows: C: 0.040%, Si: 0.14%, Mn: 1.41%, Cr: 13.94%, Ni: 24.86%, Ti: 2.27%, Al: 0.17%, Mo: 1.18%, V: 0.16%, B: 0.006%, P: 0.015%, S: 0.001%, and the rest is Fe and unavoidable impurity components.

[0058] The macrostructure, scrap metal inclusions, grain size, and mechanical properties at room temperature of the wire rods prepared in Examples 1-5 were tested, and the results were as follows:

[0059] Table 1 Macrostructure of wire rod

[0060] project General looseness (grade) Center looseness (grade) Ingot type segregation value (level) Require ≤2.0 ≤2.0 ≤2.0 Example 1 0.5 0 0 Example 2 0.5 0 0 Example 3 0.5 0 0 Example 4 1.0 1.0 1.0 Example 5 1.0 1.0 1.0

[0061] Table 2 Results of non-metallic inclusions in wire rod

[0062]

[0063] Table 3 Wire rod grain size

[0064] project Grain size (grade) Require 5-8 Example 1 6 Example 2 7-5.5 Example 3 8-5 Example 4 7-5 Example 5 7-5.5

[0065] Table 4 Mechanical properties of wire rod at room temperature

[0066] project Rm(MPa) A(％) Z(％) Require ≤620 ≥40 ≥65 Example 1 599 40.5 66 Example 2 602 41.0 67 Example 3 602 44.0 76 Example 4 591 45.0 74 Example 5 592 44.0 70

[0067] Application Example 1: This embodiment provides an application of a high temperature resistant alloy for automobile engines, using the chemical composition of the high temperature resistant alloy of Example 1, specifically including the following contents:

[0068] Preparation of high temperature resistant alloy: adopt EAF+ESR dual smelting process, put alloy raw materials and pre-desulfurized scrap steel into electric arc furnace, smelt by electricity, cast after slag removal to obtain electrode rod, transfer to electric slag furnace, add slag material for remelting and discharge to obtain electric slag ingot, forge and roll to produce square billet after homogenization annealing, roll to produce wire rod after descaling and peeling, obtain after solution annealing and pickling;

[0069] Among them, the tapping temperature of the electric arc furnace is 1675℃; the melting rate in the electric slag furnace is 8kg / min;

[0070] The homogenization annealing temperature is 1250°C, and after keeping the temperature for 8 hours, the quenching is performed to room temperature;

[0071] The solution annealing temperature is 980℃, which is kept for 1h and then water-cooled;

[0072] The chemical composition of the high temperature resistant alloy is as follows: C: 0.040%, Si: 0.26%, Mn: 0.59%, Cr: 14.04%, Ni: 24.75%, Ti: 2.18%, Al: 0.15%, Mo: 1.19%, V: 0.15%, B: 0.006%, P: 0.013%, S: 0.001%, and the rest is Fe and unavoidable impurity components.

[0073] The specific process steps for the application of high temperature resistant alloys are as follows:

[0074] 1) Selecting matrix steel and nickel-based high temperature alloy powder;

[0075] 2) Pre-treat the surface of the base steel by sanding it with sandpaper and then cleaning and drying it with acetone;

[0076] 3) Take a high temperature resistant alloy, laser clad it on the surface of the pretreated base steel to form a 2 mm iron-based cladding layer, and then perform heat treatment, solution treatment at 950 ° C for 2 hours and air cooling;

[0077] 4) taking nickel-based high-temperature alloy powder and using laser powder feeding to clad, forming a 1 mm nickel-based cladding layer on the surface of the iron-based cladding layer, aging treatment at 720° C. for 10 h, then cooling to 620° C. and keeping the temperature for 8 h, and finally air cooling to room temperature to obtain a finished product;

[0078] Among them, the laser cladding process parameters of the high-temperature resistant alloy are: argon gas flow rate is 20L / min, laser power is 1800W; spot diameter is 5mm; cladding scanning speed is 6mm / s.

[0079] The process parameters of laser powder feeding cladding of nickel-based high-temperature alloy powder are: coaxial powder feeding, argon flow rate of 20L / min, laser power of 2400W, spot diameter of 5mm, powder feeding speed of 240mg / s, and cladding scanning speed of 6mm / s.

[0080] Application Example 2: This embodiment provides an application of a high temperature resistant alloy for automobile engines, specifically including the following contents:

[0081] Preparation of high temperature resistant alloy: adopt EAF+ESR dual smelting process, put alloy raw materials and pre-desulfurized scrap steel into electric arc furnace, smelt by electricity, cast after slag removal to obtain electrode rod, transfer to electric slag furnace, add slag material for remelting and discharge to obtain electric slag ingot, forge and roll to produce square billet after homogenization annealing, roll to produce wire rod after descaling and peeling, obtain after solution annealing and pickling;

[0082] Among them, the tapping temperature of the electric arc furnace is 1675℃; the melting rate in the electric slag furnace is 8kg / min;

[0083] The homogenization annealing temperature is 1250°C, and after keeping the temperature for 8 hours, the quenching is performed to room temperature;

[0084] The solution annealing temperature is 980℃, which is kept for 1h and then water-cooled;

[0085] The chemical composition of the high temperature resistant alloy is as follows: C: 0.040%, Si: 0.10%, Mn: 0.69%, Cr: 14.01%, Ni: 24.68%, Ti: 2.10%, Al: 3.00%, Mo: 1.15%, V: 0.15%, B: 0.006%, P: 0.015%, S: 0.001%, Y: 0.2%, Ce: 0.015%, and the rest are Fe and unavoidable impurity components.

[0086] The specific process steps for the application of high temperature resistant alloys are as follows:

[0087] 1) Selecting matrix steel and nickel-based high temperature alloy powder;

[0088] 2) Pre-treat the surface of the base steel by sanding it with sandpaper and then cleaning and drying it with acetone;

[0089] 3) Take a high temperature resistant alloy, laser clad it on the surface of the pretreated base steel to form a 2 mm iron-based cladding layer, and then perform heat treatment, solution treatment at 950 ° C for 2 hours and air cooling;

[0090] 4) taking nickel-based high-temperature alloy powder and using laser powder feeding to clad, forming a 1 mm nickel-based cladding layer on the surface of the iron-based cladding layer, aging treatment at 720° C. for 10 h, then cooling to 620° C. and keeping the temperature for 8 h, and finally air cooling to room temperature to obtain a finished product;

[0091] Among them, the laser cladding process parameters of the high-temperature resistant alloy are: argon gas flow rate is 20L / min, laser power is 1800W; spot diameter is 5mm; cladding scanning speed is 5mm / s.

[0092] The process parameters of laser powder feeding cladding of nickel-based high-temperature alloy powder are: coaxial powder feeding, argon flow rate of 20L / min, laser power of 2200W, spot diameter of 5mm, powder feeding speed of 240mg / s, and cladding scanning speed of 6mm / s.

[0093] Application Example 3: This embodiment adopts the high temperature resistant alloy prepared in Application Example 2, adjusts the laser cladding parameters, and performs the following operation steps:

[0094] Preparation of high temperature resistant alloy: adopt EAF+ESR dual smelting process, put alloy raw materials and pre-desulfurized scrap steel into electric arc furnace, smelt by electricity, cast after slag removal to obtain electrode rod, transfer to electric slag furnace, add slag material for remelting and discharge to obtain electric slag ingot, forge and roll to produce square billet after homogenization annealing, roll to produce wire rod after descaling and peeling, obtain after solution annealing and pickling;

[0095] Among them, the tapping temperature of the electric arc furnace is 1675℃; the melting rate in the electric slag furnace is 8kg / min;

[0096] The homogenization annealing temperature is 1250°C, and after keeping the temperature for 8 hours, the quenching is performed to room temperature;

[0097] The solution annealing temperature is 980℃, which is kept for 1h and then water-cooled;

[0098] The chemical composition of the high temperature resistant alloy is as follows: C: 0.040%, Si: 0.10%, Mn: 0.69%, Cr: 14.01%, Ni: 24.68%, Ti: 2.10%, Al: 3.00%, Mo: 1.15%, V: 0.15%, B: 0.006%, P: 0.015%, S: 0.001%, Y: 0.2%, Ce: 0.015%, and the rest are Fe and unavoidable impurity components.

[0099] The specific process steps for the application of high temperature resistant alloys are as follows:

[0100] 1) Selecting matrix steel and nickel-based high temperature alloy powder;

[0101] 2) Pre-treat the surface of the base steel by sanding it with sandpaper and then cleaning and drying it with acetone;

[0102] 3) Take a high temperature resistant alloy, laser clad it on the surface of the pretreated base steel to form a 2 mm iron-based cladding layer, and then perform heat treatment, solution treatment at 950 ° C for 2 hours and air cooling;

[0103] 4) taking nickel-based high-temperature alloy powder and using laser powder feeding to clad, forming a 1 mm nickel-based cladding layer on the surface of the iron-based cladding layer, aging treatment at 720° C. for 10 h, then cooling to 620° C. and keeping the temperature for 8 h, and finally air cooling to room temperature to obtain a finished product;

[0104] Among them, the laser cladding process parameters of the high-temperature resistant alloy are: argon flow rate is 20L / min, laser power is 2000W; spot diameter is 5mm; cladding scanning speed is 6mm / s.

[0105] The process parameters of laser powder feeding cladding of nickel-based high-temperature alloy powder are: coaxial powder feeding, argon flow rate of 20L / min, laser power of 2000W, spot diameter of 5mm, powder feeding speed of 300mg / s, and cladding scanning speed of 6mm / s.

[0106] Application Example 4: This embodiment adopts the high temperature resistant alloy prepared in Application Example 2, adjusts the laser cladding parameters, and performs the following operation steps:

[0107] Preparation of high temperature resistant alloy: adopt EAF+ESR dual smelting process, put alloy raw materials and pre-desulfurized scrap steel into electric arc furnace, smelt by electricity, cast after slag removal to obtain electrode rod, transfer to electric slag furnace, add slag material for remelting and discharge to obtain electric slag ingot, forge and roll to produce square billet after homogenization annealing, roll to produce wire rod after descaling and peeling, obtain after solution annealing and pickling;

[0108] Among them, the tapping temperature of the electric arc furnace is 1675℃; the melting rate in the electric slag furnace is 8kg / min;

[0109] The homogenization annealing temperature is 1250°C, and after keeping the temperature for 8 hours, the quenching is performed to room temperature;

[0110] The solution annealing temperature is 980℃, which is kept for 1h and then water-cooled;

[0111] The chemical composition of the high temperature resistant alloy is as follows: C: 0.040%, Si: 0.10%, Mn: 0.69%, Cr: 14.01%, Ni: 24.68%, Ti: 2.10%, Al: 3.00%, Mo: 1.15%, V: 0.15%, B: 0.006%, P: 0.015%, S: 0.001%, Y: 0.2%, Ce: 0.015%, and the rest are Fe and unavoidable impurity components.

[0112] The specific process steps for the application of high temperature resistant alloys are as follows:

[0113] 1) Selecting matrix steel and nickel-based high temperature alloy powder;

[0114] 2) Pre-treat the surface of the base steel by sanding it with sandpaper and then cleaning and drying it with acetone;

[0115] 3) Take a high temperature resistant alloy, laser clad it on the surface of the pretreated base steel to form a 2 mm iron-based cladding layer, and then perform heat treatment, solution treatment at 950 ° C for 2 hours and air cooling;

[0116] 4) taking nickel-based high-temperature alloy powder and using laser powder feeding to clad, forming a 1 mm nickel-based cladding layer on the surface of the iron-based cladding layer, aging treatment at 720° C. for 10 h, then cooling to 620° C. and keeping the temperature for 8 h, and finally air cooling to room temperature to obtain a finished product;

[0117] Among them, the laser cladding process parameters of the high-temperature resistant alloy are: argon gas flow rate is 20L / min, laser power is 1800W; spot diameter is 5mm; cladding scanning speed is 6mm / s.

[0118] The process parameters of laser powder feeding cladding of nickel-based high-temperature alloy powder are: coaxial powder feeding, argon flow rate of 20L / min, laser power of 2000W, spot diameter of 5mm, powder feeding speed of 200mg / s, and cladding scanning speed of 6mm / s.

[0119] Testing the high temperature friction and wear performance of the products manufactured in Application Examples 1-4

[0120] The test was carried out using an HT1000 friction and wear testing machine with a friction radius of 3 mm, a spindle speed of 500 r / min, a load of 50 g, a wear time of 60 min, and a test temperature of 600 °C. The calculated wear rate data are recorded in Table 5.

[0121] Table 5

[0122]

[0123] The wire rods made from Examples 1-6 all meet the standards; the product obtained by Application Example 1 using the high-temperature resistant synthetic composition of Example 1 has slightly worse high-temperature friction and wear resistance than other application examples; the high-temperature resistant alloy composition of Application Example 2 is different from that of Example 1, with the addition of rare earth elements and the increase of the Al content, and the finished product has good high-temperature friction and wear resistance; Application Examples 2 and 3 use the high-temperature resistant alloy composition of Application Example 2, and adjust the laser cladding parameters, which has a greater impact on the high-temperature friction and wear performance of the finished product.

[0124] 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 high temperature resistant alloy for automobile engines, characterized in that: The chemical components of the high temperature resistant alloy include, by mass percentage, C: 0.03-0.08%, Si≤1.00%, Mn≤2.00%, Cr: 13.5-16.0%, Ni: 24.00-27.00%, Ti: 1.90-2.35%, Al≤0.350%, Mo: 1.00-1.50%, V: 0.10-0.50%, B: 0.003-0.010%, P≤0.015%, S≤0.001%, and the rest are Fe and unavoidable impurity components.

2. The high temperature resistant alloy for automobile engines according to claim 1, characterized in that: The chemical components of the high temperature resistant alloy include, by mass percentage, C: 0.03-0.08%, Si≤0.30%, Mn≤1.00%, Cr: 13.5-16.0%, Ni: 24.00-25.00%, Ti: 1.90-2.35%, Al: 0.10-3.00%, Mo: 1.00-1.20%, V: 0.10-0.20%, B: 0.003-0.006%, P≤0.015%, S≤0.001%, Y+Ce≤0.30%, and the rest are Fe and unavoidable impurity components.

3. A process for preparing the high temperature resistant alloy according to claim 1, characterized in that: The specific preparation process is: adopt EAF+ESR dual smelting process, put the alloy raw materials and pre-desulfurized scrap steel into an electric arc furnace, turn on the power to melt and smelt, cast to get electrode rods after slag removal, transfer to the electric slag furnace for remelting, get electric slag ingots, forge and roll to make square billets after homogenization annealing, roll to make wire rods after descaling and peeling, and pickle after solution annealing.

4. The preparation process according to claim 3, characterized in that: The steel-out temperature of the electric arc furnace is 1650-1675° C.; the slag added to the electric slag furnace includes the following raw materials by mass percentage: CaF2: 50-70%, Al2O3: 10-20%, CaO: 0-10%, TiO2: 8-10%; the melting rate is 8-10kg / min.

5. The preparation process according to claim 3, characterized in that: The temperature of homogenization annealing is 1225-1275°C, and it is kept warm for 6-8 hours; the temperature of solution annealing is 950-1000°C, and it is kept warm for 1 hour and then water-cooled.

6. An application of a high temperature resistant alloy for an engine, characterized in that: The following steps are involved: 1) Pre-treat the surface of the base steel by sanding it with sandpaper and then cleaning and drying it with acetone; 2) taking the high temperature resistant alloy according to claim 1, laser cladding the surface of the pretreated base steel to form an iron-based cladding layer, and then performing heat treatment; 3) Taking nickel-based high-temperature alloy powder, laser powder feeding is used for cladding to form a nickel-based cladding layer on the surface of the iron-based cladding layer, and aging treatment is performed to obtain a finished product.

7. The use of a high temperature resistant alloy for an engine according to claim 6, characterized in that: The process parameters of laser cladding of high-temperature resistant alloys are: argon flow rate is 20L / min-30L / min, laser power is 1500W~1800W, spot diameter is 5mm, and cladding scanning speed is 4mm / s~6mm / s.

8. The use of a high temperature resistant alloy for an engine according to claim 6, characterized in that: The process parameters of the laser powder cladding are: coaxial powder feeding, argon gas flow rate of 20L / min-30L / min, laser power of 2000W-2400W; spot diameter of 5mm; defocus of the laser cladding head of +15mm-+30mm, powder feeding speed of 200mg / s-300mg / s, and cladding scanning speed of 4mm / s-6mm / s.

9. The use of a high temperature resistant alloy for an engine according to claim 6, characterized in that: The thickness of the iron-based cladding layer is 2 mm; the thickness of the nickel-based cladding layer is 1 mm; the heat treatment process parameters are: solution treatment at 950-980°C for 1-2 hours and then air cooling; the aging treatment process parameters are: aging treatment at 720-750°C for 8-10 hours, then cooling to 600-620°C for 8-10 hours, and finally air cooling to room temperature.

10. The use of a high temperature resistant alloy for an engine according to claim 6, characterized in that: The chemical components of the base steel include, by mass percentage, C≤0.03%, Mn≤2.00%, Cr: 16-18%, Ni: 10-14%, Mo: 2.00-3.00%, and the rest are Fe and inevitable impurity components; the chemical components of the nickel-based high-temperature alloy powder include, by mass percentage, C: 0.03-0.04%, Cr: 17-21%, Ni: 50.00-55.00%, Ti: 0.65-1.15%, Al: 0.2-0.8%, Nb+Ta: 4.75·5.5%, Mo: 2.8-3.3%, and the rest are Fe and inevitable impurity components.

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