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CN-122007440-A - Preparation method of Fe-Mn-Al-Ni-C light steel alloy

CN122007440ACN 122007440 ACN122007440 ACN 122007440ACN-122007440-A

Abstract

The invention relates to the technical field of laser additive manufacturing, in particular to a preparation method of Fe-Mn-Al-Ni-C light steel alloy. Preparing materials according to the component proportion, preparing Fe-Mn-Al-Ni-C alloy powder by adopting a vacuum induction melting gas atomizing furnace, a tightly coupled nozzle and powder screening equipment, presetting the alloy powder on the surface of a base material, setting the laser additive manufacturing process parameters of the Fe-Mn-Al-Ni-C alloy, printing and stacking the Fe-Mn-Al-Ni-C alloy layer by layer, and performing heat treatment on the Fe-Mn-Al-Ni-C alloy manufactured by laser additive. By matching accurate component regulation and control with a subsequent heat treatment process, the material realizes high strength level with yield strength more than or equal to 900MPa and ultimate tensile strength more than or equal to 1GPa on the basis of low density, and solves the technical problem of 'density loss reduction and strength' commonly existing in light steel.

Inventors

  • YANG JUNWEI
  • CUI YUFEI
  • REN ZITING
  • Liu Congpeng
  • GENG XIAODONG
  • WU JINYANG
  • ZHANG KE
  • WANG GANG
  • XUE JIANSHU
  • JING JUNFENG

Assignees

  • 阳泉煤业集团华越机械有限公司

Dates

Publication Date
20260512
Application Date
20260303

Claims (10)

  1. 1. A preparation method of Fe-Mn-Al-Ni-C light steel alloy is characterized by comprising the following specific steps: S1, preparing materials according to the component proportion, and preparing Fe-Mn-Al-Ni-C alloy powder by adopting a vacuum induction melting gas atomization furnace, a tightly coupled nozzle and powder screening equipment; s2, presetting Fe-Mn-Al-Ni-C alloy powder on the surface of a substrate; S3, setting the laser additive manufacturing process parameters of the Fe-Mn-Al-Ni-C alloy, and printing and stacking the Fe-Mn-Al-Ni-C alloy layer by layer; S4, performing heat treatment on the Fe-Mn-Al-Ni-C alloy manufactured by laser additive.
  2. 2. The method for preparing the Fe-Mn-Al-Ni-C light steel alloy according to claim 1, wherein the component proportion of the S1 is 10-35 wt.% Mn, 3-13 wt.% Al, 4-14 wt.% Ni, 0.3-1.5 wt.% C and the balance Fe.
  3. 3. The method for preparing the Fe-Mn-Al-Ni-C light steel alloy, which is characterized in that the vacuum induction melting gas atomization furnace in the step S1 is at the melting temperature of 1580-1620 ℃ and the heat preservation time is 15-30 min.
  4. 4. The preparation method of the Fe-Mn-Al-Ni-C light steel alloy is characterized in that the alloy powder is obtained after atomizing and cooling for 40min under the conditions that the atomizing pressure of a tightly coupled nozzle in S1 is 3MPa and the metal diversion speed is 16 kg/min.
  5. 5. The method for preparing the Fe-Mn-Al-Ni-C light steel alloy according to claim 1, wherein the screening device in S1 screens the powder particle size into D10=14μm+ -7μm, D50=36μm+ -10μm, D90=65μm+ -10μm and vacuum-dried at 80-120 ℃ for 1h and then vacuum-packaged.
  6. 6. The method for preparing the Fe-Mn-Al-Ni-C light steel alloy according to claim 1, wherein the preset mode in the step S2 is blade coating, the thickness of a single-layer powder bed is 36 mu m plus or minus 10 mu m, and the preheating temperature of a base material is 100-300 ℃.
  7. 7. The method for preparing the Fe-Mn-Al-Ni-C light steel alloy according to claim 1, wherein the laser power in the S3 is 80W-140W, the scanning speed of a vibrating mirror is 700mm/S-1200mm/S, the lap joint rate is 40% -70%, the laser spot size is 55 μm-100 μm, and the laser scanning deflection angle is 0-180 degrees.
  8. 8. The method for preparing the Fe-Mn-Al-Ni-C light steel alloy, which is characterized in that the content of ambient oxygen in the laser additive manufacturing process in the S3 is less than or equal to 100ppm, and the scanning path is one or more of Z-shaped, S-shaped, annular or gyroid.
  9. 9. The method for preparing the Fe-Mn-Al-Ni-C light steel alloy according to claim 1, wherein the S4 heat treatment is annealing heat treatment, the temperature range is 1000-1200 ℃, the heat preservation time is 0.5-2 h, and the cooling mode is furnace cooling.
  10. 10. The method for preparing the Fe-Mn-Al-Ni-C light steel alloy according to claim 1, wherein the heat treatment in the step S4 is aging treatment, the temperature is 600-700 ℃, the heat preservation time is 2-6 h, and when the temperature of the aging treatment is 600-650 ℃, the preferable heat preservation time is 3-6 h.

Description

Preparation method of Fe-Mn-Al-Ni-C light steel alloy Technical Field The invention relates to the technical field of laser additive manufacturing, in particular to a preparation method of Fe-Mn-Al-Ni-C light steel alloy. Background Along with the increasingly urgent demands for energy conservation, weight reduction and performance improvement in the fields of high-end equipment such as aerospace, rail transit, new energy automobiles and the like, the light weight has become one of the core directions of advanced material development. As a main stream material of a key bearing structural member, the lightweight design of the steel material has great strategic significance and application value. In this context, light-weight steel of Fe-Mn-Al-C system, which is characterized by high specific strength, has been attracting attention. The steel can effectively maintain or improve the mechanical properties by adding light elements such as Mn, al and the like in a higher proportion to replace part of traditional alloy elements, obviously reduce the density of the material and simultaneously by means of the strengthening effect of various nano-grade precipitated phases such as kappa-carbide and B2 and the like, and has good comprehensive performance potential and economic advantages. However, the composition design of lightweight steels presents typical performance trade-offs. Research shows that the density of the material continuously decreases along with the increase of the content of the density-reducing elements such as Al, but the key mechanical indexes such as room temperature, high temperature strength and plasticity of the material can be obviously attenuated, and the work hardening behavior, the phase change characteristic and the final tissue state of the material also change in a complex manner. Therefore, how to realize the synergy of high strength and high toughness while ensuring low density through the accurate design and micro-alloying of the multi-component components is the first scientific problem facing the current light steel material research and development. Meanwhile, advanced forming technology represented by laser additive manufacturing provides a brand new way for the integral and high-performance manufacturing of light steel parts with complex structures. The technology is particularly suitable for the requirement of the aerospace field on customized and lightweight components by virtue of the characteristics of high flexibility, rapid forming and near-net forming. However, light weight steels, particularly those with high aluminum content, face significant process challenges in laser additive manufacturing processes. In addition, the extremely unbalanced thermal cycle which is peculiar to the laser rapid fusing is extremely easy to cause the segregation of elements such as Al, mn and the like on microscopic scale, so that the uneven structure, abnormal phase composition and precipitation of harmful brittle phases are caused, thereby severely restricting the reliability and consistency of the mechanical properties of the component. Disclosure of Invention The invention aims at solving at least one of the technical problems existing in the prior art, and therefore, one aspect of the invention aims at providing a preparation method of Fe-Mn-Al-Ni-C light steel alloy, which comprises the following specific steps: S1, preparing materials according to the component proportion, and preparing Fe-Mn-Al-Ni-C alloy powder by adopting a vacuum induction melting gas atomization furnace, a tightly coupled nozzle and powder screening equipment; s2, presetting Fe-Mn-Al-Ni-C alloy powder on the surface of a substrate; S3, setting the laser additive manufacturing process parameters of the Fe-Mn-Al-Ni-C alloy, and printing and stacking the Fe-Mn-Al-Ni-C alloy layer by layer; S4, performing heat treatment on the Fe-Mn-Al-Ni-C alloy manufactured by laser additive. Preferably, the composition ratio in the S1 is 10wt.% to 35wt.% Mn, 3wt.% to 13wt.% Al, 4wt.% to 14wt.% Ni, 0.3wt.% to 1.5wt.% C, and the balance being Fe. Preferably, the vacuum induction melting gas atomization furnace in the step S1 has a melting temperature of 1580-1620 ℃ and a heat preservation time of 15-30 min. Preferably, in the step S1, the alloy powder is obtained after atomization cooling for 40min under the condition that the atomization pressure of the tightly coupled nozzle is 3MPa and the metal diversion speed is 16 kg/min. Preferably, the screening device in S1 screens the powder particle size into d10=14μm±7μm, d50=36μm±10μm, d90=65μm±10μm, and vacuum-drying at 80 ℃ to 120 ℃ for 1h and vacuum-packaging. Preferably, the preset mode in the step S2 is knife coating, the thickness of the single-layer powder bed is 36 mu m plus or minus 10 mu m, and the preheating temperature of the base material is 100-300 ℃. Preferably, in the step S3, the laser power is 80W-140W, the scanning speed of the vibrating mirror is 700mm/S-1200mm/S, the