工业纯钛喷丸强化研究

Investigation on the Shot Peening of Commercial Pure-Titanium

摘要:

采用TEM结合SEM和XRD对工业纯钛喷丸强化后显微组织结构、断口形貌、残余应力进行分析，研究了影响疲劳性能的3个因素即：组织、应力、粗糙度。结果表现：孪生是六方合金的塑性变形主要形式，喷丸强化表层形变组织由孪晶和变形带构成，表层孪晶间强烈交互作用，可造成显微损伤；表层残余应力在疲劳后发生明显松驰，有益贡献也相应的降低；表面粗糙度提高，具有负的影响。

关键词:喷丸强化 变形孪晶 残余应力 工业纯钛

Abstract:

The substructure, fracture morphology and residual stress of shot peened commercial pure titanium were analyzed by the methods of TEM, SEM and XRD. The structure, stress and roughness affecting the fatigue strength were studied in this paper. The results show that twinning plays an important role in plastic deformation of hcp metals, the shot peening layer consists of twins and deformation bands, and the twin interactions can cause micro damage. Fatigue would relax the residual stresses and decrease the strengthening effect. The increased surface roughness has negative effects.

Key words:titanium,shot peening,deformation twin,residual stress