不锈钢-碳钢层合板激光弯折区的热传导特性

Heat Conduction Characteristics of Stainless Steel-Carbon Steel Laminated Sheet Bending Position

金属层合板复层与基层物理特性存在差异,激光弯折区特性异于单一板材。为研究层间热传导特性,选取不锈钢-碳钢层合板进行激光弯曲实验。观察分析不同累积线能量下不锈钢层合板弯折区的金相组织,利用IPP图像处理软件划分热影响区,分析层间热传导特性。层间热导率差异使得层间热传导速率减缓,碳钢层热影响区呈现扁平抛物线梯度分布,并于下界面处出现热累积现象。层间热传导特性通过影响层间温度梯度及塑性变形区域实现层合板不同角度的弯曲。热传导特性研究为提高层合板激光弯曲精度与质量提供理论和实验依据。

Due to difference in the physical property between the base layer steel and the cover layer steel, laser bending area characteristics of the dissimilar metal laminated plates are different with the single sheet. Metallographic structures of laser bending areas in stainless steel-carbon steel laminated sheets under different accumulative line energy are analysed in order to study heat conduction mode between the layers. By aking use of IPP image processing software to divide the heat-affected zone （HAZ）, then energy transfer mode is analyzed. Heat transfer rate slows down because of thermal conductivity difference between the layers. Heat-affected areas present flat parabolic graded distribution in the mild carbon steel layer, and heat accumulation occurs on the lower surface. Bending angles of laminated sheets are determined by plastic deformation area and temperature gradient between the layers affected by heat conduction mode. Studies of heat conduction mode of stainless steel-carbon steel laminated sheets provide the basis of theory and experiment for better bending precision and quality.