表面状态对疲劳塑性变形局部化的影响

发布时间：2018-06-25 02:35

本文选题：WaspaloyTM高温镍基合金 + 表面粗糙度　；参考：《表面技术》2017年02期

【摘要】：目的研究不同的表面状态对Waspaloy~(TM)镍基高温合金塑性变形局部化的影响,确定最优的评价塑性应变局部化的三维表面粗糙度参数。方法对两组Waspaloy~(TM)高温镍基合金先进行机械抛光至0.02mm,然后分别进行电解抛光和化学蚀刻,得到不同的两种表面状态。通过制作标准试样进行疲劳试验得到疲劳寿命,并采用原子力显微镜、扫描电子显微镜和三维表面轮廓仪分析Waspaloy~(TM)镍基高温合金在电解抛光和化学蚀刻处理前后的表面形貌以及裂纹萌生形貌。结果试样经过电解抛光和化学蚀刻后,电解抛光表面质量更好,三维表面粗糙度Sa(表面算数平均偏差)分别是0.001、0.018mm,经过疲劳试验后的值分别为0.024、0.026mm,表面粗糙度参数Sp(表面最大峰高)均为0.131mm。电解抛光试样的疲劳寿命为800,化学蚀刻试样的疲劳寿命为700。经过化学蚀刻和电解抛光的试样疲劳裂纹均是从滑移带处开始产生,并沿滑移带扩展。结论表面状态影响材料的疲劳寿命,表面粗糙度小的试样疲劳寿命长。三维表面粗糙度参数Sp适用于描述材料疲劳塑性应变局部化,其临界值揭示了材料裂纹萌生。
[Abstract]:Objective to study the effect of different surface states on the plastic deformation localization of Waspaloy~ (TM) nickel base superalloy, and to determine the optimum parameters for evaluating the three-dimensional surface roughness of the plastic strain localization. Two groups of Waspaloy~ (TM) high temperature nickel base alloys were mechanically polished to 0.02mm, and then electrochemical polishing and chemical etching were performed respectively. The fatigue life of the Waspaloy~ (TM) nickel base superalloy Waspaloy~ (TM) was analyzed by atomic force microscopy, scanning electron microscope and three-dimensional surface profilometer. The results of the specimen were analyzed by the atomic force microscope, scanning electron microscope and three-dimensional surface profilometer. After electropolishing and chemical etching, the surface quality of the electrolytic polishing is better, the surface roughness Sa (average deviation of the surface calculation) is 0.001,0.018mm respectively. After the fatigue test, the value is 0.024,0.026mm respectively. The surface roughness parameter Sp (the maximum height of the surface) are all the fatigue life of the 0.131mm. electrolytic polishing sample, and the chemical etching test is 800. The fatigue life of samples whose fatigue life is 700. through chemical etching and electrolytic polishing is started from the slip zone and extends along the slip zone. Conclusion the surface state affects the fatigue life of the material, and the fatigue life of the sample with small surface roughness is long. The three-dimensional surface roughness parameter Sp is suitable for describing the local fatigue plastic strain local. The critical value reveals the crack initiation of the material.
【作者单位】：郑州大学机械工程学院;
【基金】：河南省高等学校重点科研项目(15A460030)~~
【分类号】：TG132.3

【相似文献】