机械振动作用下铁基涂层熔覆角的模型构建及其变化规律研究

Cladding Angle Model and Variation Law of Fe-Based Coating Fabricated by Mechanical Vibration Assisted Laser Cladding

采用机械振动辅助激光熔覆工艺在45钢表面制备了Fe55合金涂层,通过光学图像分析仪观察了熔覆层的几何形貌,结合Auto CAD软件标注了涂层高度、宽度和熔覆角等几何特征参数,探讨了激光比能、振幅、频率等工艺参数对涂层熔覆角的影响,借助响应面分析法提供的二阶多项式构建了能明确表征熔覆角与激光比能、振幅、频率之间隐式关系的函数模型。结果表明,机械振动作用下激光熔覆层的熔覆角大于无机械振动的涂层。在相同激光比能和振幅条件下,频率200 Hz比频率100 Hz的熔覆角大,且在振幅为0.10 mm时熔覆角最小。采用最小二乘法优化后的函数模型所计算的熔覆角优于现有几何模型计算值,更接近实际测量结果。

Fe55 alloy coating is fabricated on 45 steel surface through laser cladding assisted mechanical vibration process. The geometry morphology of cladding coating is observed by optical microscrope. Utilizing Auto CAD, geometry parameters of cladding coating height, width and cladding angle are marked to explore the effects of laser specific energy, amplitude and frequency of mechanical vibration on cladding angle. By means of second-order polynomial of response surface analysis method, a function model being able to express the relationship among cladding angle, laser specific energy, amplitude and frequency is established. Results show that the cladding angle of laser cladding coating is greater when combined with mechanical vibration. Provided with the same laser specific energy and amplitude of vibration, the cladding angle under frequency of 200 Hz is larger than the one with frequency of 100 Hz, and the cladding angle reaches the minimum value when the amplitude is 0.10 mm. The calculated value of cladding angle using the least squares function models is superior to the existing geometry model by being closer to the actual measurement result.