郭火明
,
王文健
,
刘腾飞
,
郭俊
,
刘启跃
材料热处理学报
利用滚动磨损试验机研究了激光相变硬化处理前后轮轨钢试样的磨损与损伤性能.结果表明:激光相变硬化处理主要得到马氏体组织,显著提高轮轨试样的表面硬度,钢轨试样和车轮试样分别提高43.06％、44.39％;轮轨试样经激光相变硬化处理后滚动摩擦系数与未处理试样相差不大,单一处理轮轨试样摩擦系数有所增大;轮轨试样经激光相变硬化处理能明显提高轮轨试样表面抗磨损和变形能力,车轮试样磨损率减少约44.02％,钢轨试样减少约13.6％,单一处理轮轨试样虽能降低处理试样的磨损,但显著加剧对摩副的磨损;激光相变硬化处理后,钢轨试样表现为轻微疲劳磨损,车轮试样则是粘着磨损与疲劳磨损共存,以疲劳磨损为主;重载工况下轮轨钢试样均激光相变硬化处理能有效改善材料抗磨损和损伤能力.
关键词:
轮轨
,
激光相变硬化
,
磨损率
,
损伤
L. W Zhang
,
R.S. Wang
,
J. Th.M.De Hosson
,
Y.L. Xia and F. G. Wang 1) The State Key Lab. for Materials Modification by Laser
,
Ion and Electron Beams
,
Dalian University of Technology
,
Dalian 116023
,
China 2) Department of Applied Physics
,
University of Groningen
,
The Netherlands
金属学报(英文版)
A three-dimensional transient heat transfer model for laser transformation hardening process has been developed in this paper. The finite size of the laser treated sample, the surface heat loss of the sample, the latent heat of phase transformation and the temperature dependence of thermal properties of materials were considered. The heat source was considered as a moving Gaussian heat flux with a constant velocity. Three-dimension unequally spatial grid explicit finite difference equations, alternating direction implicit finite difference equations and implicit finite difference equations were deduced respectively. Three programs to calculate the temperature field were developed using Fortran language. The transient temperature fields of C22, 42CrMo, C60 steel samples during laser transformation hardening process were calculated using these programs, and the widths and depths of laser transformation hardening zones were also predicted. C22, 42CrMo, C60 steel samples were treated by CO_2 laser,the widths and depths of laser transformation hardening zones of these samples were also measured experimentally. The calculated widths and depths of laser transformation hardening zones are in good agreement with the experimental results.
关键词:
temperature field
,
null
,
null
