喷丸强化对18Cr2Ni4WA渗碳钢性能的影响

Effect of Shot Peening Treatment on the Performance of 18Cr2Ni4WA Steel

采用强力喷丸工艺对渗碳18Cr2Ni4WA钢试样进行了表面喷丸强化处理。利用Nano Test 600纳米测试仪、2903X射线应力仪和TR200表面粗糙度仪，分别测试分析了试样处理前后的显微硬度、残余应力和表面粗糙度，并在JP-52接触疲劳试验机上考察了喷丸强化处理对渗碳18Cr2Ni4WA钢接触疲劳性能的影响。试验结果表明：渗碳试样经强力喷丸后，在0～0．50mm深的表层内形成一个喷丸硬化层，显微硬度提高了约1．1GPa；最大残余压应力由-478 MPa提高到-760 MPa；表面粗糙度由1．255μm降为0．979μm。接触疲劳特征寿命以与中值寿命L50均提高了2倍多，额定寿命L10提高了1倍多。

Carburized 18Cr2Ni4WA steel samples are treated by shot peening techniques. Then effect of shot peening treatment on the properties （such as microhardness, residual stress, roughness, contact fatigue life） of carburized 18Cr2Ni4WA steel are investigated by Nano Test 600, 2903X-ray stress apparatus, TR200 surface roughness instrument and JP-52 contact fatigue instrument. Results of the tests show that, because of shot peening, a thick hard layer between 0 mm and 0.50 mm on the surface of carburied samples is formed and the microhardness is enhanced by 1.1 GPa. The residual stress is changed from -478 MPa to -760 MPa and roughness is reduced from 1. 255 μm to 0.979 μm. Contact fatigue tests show that eigenlife Vs, medianlife L50 are prolonged respectively by 2 times and ratinglife L10 is prolonged by 1 time by shot peening.