【摘要】 通过建立Q235钢表面激光熔覆低碳铁基合金温度场三维模型,分析了熔覆层顶、底的温度随时间变化的曲线,由此对熔覆层成形质量进行预测。结合实验论证得到激光功率为2000W、扫描速度为10mm/s时,熔覆层顶、底点最高温度分别为2300℃和1500℃,有利于得到表面形貌较好、与基体良好冶金结合的熔覆层,熔覆层组织由等轴晶和垂直于界面的树枝晶构成,过渡区为富Cr、Ni的板条状马氏体;熔覆区组织均匀致密,过渡区中基体和熔覆材料产生了良好冶金结合且稀释率低,热影响区铁素体与珠光体得到了细化。更多还原

【Abstract】 Based on the 3-dimensional model of laser cladding with low carbon iron alloy on Q235 steel’s surface,the change of temperature from the top to the bottom of cladding layer was analyzed and the quality of cladding was predicted.Experimental results show that when the laser power is 2000 Wand the scanning speed is 10 mm/s,the temperatures at the top and bottom of the cladding layer are around 2300℃and 1500℃,which are favorable to get nice surface morphology,the cladding layer is composed of equiaxed crystal and dendrites crystal perpendicular to the interface.The transition zone is composed of louticular martensite in which Cr and Ni are rich.The microstructure of the cladding zone is uniform and compact.The matrix and cladding materials are well metallurgically bonded and have a low dilution rate.The ferrite and pearlite in the heat affected zone are refined.更多还原