發(fā)布時(shí)間：2019-05-17 04:06

【摘要】：為了研究面心立方金屬在熱力耦合作用下的微觀組織,采用分子動力學(xué)方法對激光溫噴丸在單晶銅內(nèi)誘導(dǎo)的位錯(cuò)擴(kuò)展進(jìn)行了模擬,并使用中心對稱參數(shù)研究了變形量對位錯(cuò)擴(kuò)展的影響規(guī)律,以及溫度對塑性變形誘導(dǎo)位錯(cuò)擴(kuò)展的作用,進(jìn)而從加工硬化的角度分析了其對激光溫噴丸強(qiáng)化效果的影響。結(jié)果表明,激光溫噴丸過程中,塑性變形以"空位簇-不全位錯(cuò)-堆垛層錯(cuò)"的方式誘導(dǎo)產(chǎn)生不全位錯(cuò)與堆垛層錯(cuò)。隨塑性變形增加,激光溫噴丸的硬化效果逐漸增加。并且,溫度可以促進(jìn)塑性變形過程中位錯(cuò)的形核與擴(kuò)展,200℃以內(nèi),激光溫噴丸的硬化效果隨溫度的增加而增強(qiáng),溫度增至250℃時(shí),硬化效果由于位錯(cuò)湮滅而減弱。
[Abstract]:In order to study the microstructure of face-centered cubic metal under thermal coupling, the dislocation propagation induced by laser warm shot peening in single crystal copper was simulated by molecular dynamics method. The influence of deformation on dislocation propagation and the effect of temperature on dislocation propagation induced by plastic deformation are studied by using central symmetry parameters, and then the effect of temperature on laser warm shot peening strengthening is analyzed from the point of view of working hardening. The results show that incomplete dislocation and stacking fault are induced by "vacancy cluster-incomplete dislocation-stacking fault" in the process of laser warm shot peening. With the increase of plastic deformation, the hardening effect of laser warm shot peening increases gradually. Moreover, temperature can promote the nucleation and expansion of dislocations in the process of plastic deformation. Within 200 鈩，

本文編號：2478789