【摘要】：采用SYSWELD軟件建立激光熔覆Ni-WC-Cr3C2涂層的熱應(yīng)力分析的有限元模型,通過熔池形貌對(duì)比驗(yàn)證模型的可靠性。利用建立的模型,進(jìn)一步分析陶瓷涂層冷卻階段溫度梯度和應(yīng)力場(chǎng)的變化規(guī)律及基板預(yù)熱對(duì)溫度梯度和應(yīng)力分布的影響。結(jié)果表明,激光熔覆處理是經(jīng)歷了快速加熱、快速冷卻的過程,陶瓷涂層內(nèi)呈拉應(yīng)力狀態(tài),極易沿垂直掃描方向發(fā)生脆性開裂�；孱A(yù)熱可以顯著降低陶瓷涂層的冷卻速度,且預(yù)熱溫度越高,冷卻速度降低越明顯,涂層內(nèi)應(yīng)力也隨之降低。預(yù)熱350℃及以上可以有效抑制裂紋產(chǎn)生。
[Abstract]:The finite element model of thermal stress analysis of laser cladding Ni-WC-Cr3C2 coating was established by SYSWELD software. The reliability of the model was verified by comparing the morphology of molten pool. By using the established model, the variation of temperature gradient and stress field in the cooling stage of ceramic coating and the effect of substrate preheating on temperature gradient and stress distribution were analyzed. The results show that the laser cladding process goes through the process of rapid heating and rapid cooling, and the ceramic coating exhibits tensile stress state, and brittleness cracking easily occurs along the vertical scanning direction. Substrate preheating can significantly reduce the cooling rate of ceramic coating, and the higher the preheating temperature, the lower the cooling rate and the lower the internal stress of the coating. Preheating at 350 鈩，

本文編號(hào)：2171332