Ti-6Al-4V alloy was processed by wet shot peening with ceramic beads. The effects of the shot peened intensity on the microstructure, surface morphology, and residual stress were investigated. A tensile-tensile fatigu...Ti-6Al-4V alloy was processed by wet shot peening with ceramic beads. The effects of the shot peened intensity on the microstructure, surface morphology, and residual stress were investigated. A tensile-tensile fatigue test was performed and the fracture mechanism was proposed. The results demonstrate that the surface roughness after wet shot peening is obviously lower than that after dry shot peening. With the increase of the shot peened intensity, the depth of the residual stress layer increases to 250 ktrn, and the maximum stress in this layer increases to -895 MPa. The fatigue strength also increases by 12.4% because of the wet shot peening treatment. The dislocation density of the surface layer is significantly enhanced after the wet shot peening with ceramic beads. The microstructure of the surface layer is obviously refined into ultra-fine grains.展开更多
采用湿喷丸技术处理铝合金表面,研究喷丸强度对2219铝合金扩散连接的影响。结果表明:随着喷丸强度的提高,表面粗糙度由0.1 mm N的1.917μm增加到0.3 mm N的3.401μm,且过大的喷丸强度易导致表面出现轻微的剥落损伤现象;喷丸强化提供的...采用湿喷丸技术处理铝合金表面,研究喷丸强度对2219铝合金扩散连接的影响。结果表明:随着喷丸强度的提高,表面粗糙度由0.1 mm N的1.917μm增加到0.3 mm N的3.401μm,且过大的喷丸强度易导致表面出现轻微的剥落损伤现象;喷丸强化提供的残余应力场可以促进界面的扩散连接过程,一方面加速溶质原子扩散并在界面聚集成相且与氧化物产生交互作用;另一方面促进再结晶晶粒形成,利用新晶界的动态迁移过程消除原始界面,两者共同作用提升了界面的愈合效果,0.1 mm N时界面剪切强度可由无喷丸的12.6 MPa提升至41.1 MPa。展开更多
采用陶瓷湿喷丸强化技术对TC4合金进行表面改性处理,研究湿喷丸强度对钛合金表面状态及拉拉疲劳寿命的影响规律。结果表明,湿喷丸强化在材料表面引入残余压应力场,随喷丸强度增加残余压应力层变深。喷丸强度为0.1～0.2 mm N时,材料表面...采用陶瓷湿喷丸强化技术对TC4合金进行表面改性处理,研究湿喷丸强度对钛合金表面状态及拉拉疲劳寿命的影响规律。结果表明,湿喷丸强化在材料表面引入残余压应力场,随喷丸强度增加残余压应力层变深。喷丸强度为0.1～0.2 mm N时,材料表面机加工痕迹得到有效去除,且表面粗糙度降低。湿喷丸强化后,材料表层位错密度增加,晶粒细化。湿喷丸强化能够明显改善TC4合金疲劳性能,改善效果和喷丸强度间不是单调关系,即存在最优喷丸工艺参数。在喷丸强度0.3 mm N条件下,疲劳寿命是基材的1.93倍,改善效果最明显。展开更多
基金Project(NCET-10-0278)supported by Program for New Century Excellent Talents in University,China
文摘Ti-6Al-4V alloy was processed by wet shot peening with ceramic beads. The effects of the shot peened intensity on the microstructure, surface morphology, and residual stress were investigated. A tensile-tensile fatigue test was performed and the fracture mechanism was proposed. The results demonstrate that the surface roughness after wet shot peening is obviously lower than that after dry shot peening. With the increase of the shot peened intensity, the depth of the residual stress layer increases to 250 ktrn, and the maximum stress in this layer increases to -895 MPa. The fatigue strength also increases by 12.4% because of the wet shot peening treatment. The dislocation density of the surface layer is significantly enhanced after the wet shot peening with ceramic beads. The microstructure of the surface layer is obviously refined into ultra-fine grains.
文摘采用湿喷丸技术处理铝合金表面,研究喷丸强度对2219铝合金扩散连接的影响。结果表明:随着喷丸强度的提高,表面粗糙度由0.1 mm N的1.917μm增加到0.3 mm N的3.401μm,且过大的喷丸强度易导致表面出现轻微的剥落损伤现象;喷丸强化提供的残余应力场可以促进界面的扩散连接过程,一方面加速溶质原子扩散并在界面聚集成相且与氧化物产生交互作用;另一方面促进再结晶晶粒形成,利用新晶界的动态迁移过程消除原始界面,两者共同作用提升了界面的愈合效果,0.1 mm N时界面剪切强度可由无喷丸的12.6 MPa提升至41.1 MPa。
文摘采用陶瓷湿喷丸强化技术对TC4合金进行表面改性处理,研究湿喷丸强度对钛合金表面状态及拉拉疲劳寿命的影响规律。结果表明,湿喷丸强化在材料表面引入残余压应力场,随喷丸强度增加残余压应力层变深。喷丸强度为0.1～0.2 mm N时,材料表面机加工痕迹得到有效去除,且表面粗糙度降低。湿喷丸强化后,材料表层位错密度增加,晶粒细化。湿喷丸强化能够明显改善TC4合金疲劳性能,改善效果和喷丸强度间不是单调关系,即存在最优喷丸工艺参数。在喷丸强度0.3 mm N条件下,疲劳寿命是基材的1.93倍,改善效果最明显。
