喷丸强化对TC21高强度钛合金疲劳性能的影响  

Influence of shot peening on fatigue property of TC21 titanium alloy

作　　者：高玉魁[1] 

机构地区：[1]北京航空材料研究院,北京100095

出　　处：《金属热处理》2010年第8期30-32,共3页Heat Treatment of Metals

摘　　要：对TC21疲劳试样进行喷丸,测定未强化试样和喷丸强化试样的旋转弯曲疲劳S-N曲线和采用升降法测定1×107周次下的条件疲劳极限,利用X射线应力仪测定了残余应力,用扫描电镜分析了疲劳断口。试验结果表明,喷丸不仅可显著延长TC21钛合金的疲劳寿命和提高疲劳强度,而且能使疲劳裂纹不再从表面萌生而是从表面强化层下的基体材料处形成并向四周扩展。The TC21 fatigue specimens were shot peened and S-N curves of the unpeened and shot-peened specimens were tested by rotating bending fatigue.The fatigue limits of the unpeened and shot-peened specimens under 1×107cycles were determined by stair-step method.Moreover,the residual stresses in the surface hardened layer were analyzed by X-ray diffraction with polishing layer by layer,and fatigue fractographs were observed by SEM.The results show that the shot peening can enhance the fatigue strength and prolong fatigue life,and the fatigue crack source are located under the surface hardened layers.

关 键 词：TC21钛合金 喷丸 残余应力 疲劳性能 

分 类 号：TG142.1[一般工业技术—材料科学与工程]