堆焊双金属冷镦粗过程中的变形行为

借助冷镦粗实验研究堆焊双金属在大塑性变形下的变形行为,进而探索堆焊双金属坯料锻造成形的可行性。首先使用等离子弧喷焊技术制备双金属坯料,测定堆焊双金属熔覆层区域的显微硬度,认知堆焊双金属材料的界面特性;随后分析冷镦粗过程中堆焊双金属试样的变形与破坏方式。结果表明:堆焊双金属的显微硬度最薄弱区域出现在熔合线附近,熔覆层区域整体硬度远高于基体硬度;冷镦粗过程中,堆焊双金属基体区域率先发生塑性变形,熔覆层抵抗变形的能力高于基体;压缩到一定阶段,熔覆层底部区域也会发生塑性变形,熔覆层区域具有进行塑性变形的潜力。

Deformation behavior of surfacing welding bimetal in cold upsetting process

The deformation behavior of surfacing welding bimetal under large plastic deformation was studied by the cold upsetting experi-ment, and the feasibility of forging surfacing welding bimetal was explored. Firstly, the bimetal billet was prepared by PTA spray welding, and the microhardness near the cladding layer of surfacing welding bimetal was measured to estimate the interfacial properties of surfacing welding bimetal. Then, the deformation and failure mode of surfacing welding bimetal in the cold upsetting process were investigated. The results show that the weakest microhardness region of surfacing welding bimetal appears near the fusion line, and the microhardness of cladding layer is much higher than that of substrate. Furthermore, in the cold upsetting process, the plastic deformation firstly occurs in the substrate region of surfacing welding bimetal, and the ability of cladding layer resisting deformation is higher than that of substrate. Therefore, when compression is up to a certain stage, the plastic deformation occurs at the bottom of the cladding layer, and the cladding layer region has the potential for plastic deformation.