等离子弧异质异构增材制造构件的组织与力学性能分析

Study on plasma arc additive manufacturing process of dissimilar steels with various composite structures

关键词:  异质增材制造  异构  高强钢/不锈钢  交替叠合  力学性能

Key words:  heterogeneous additive manufacturing  various composite structures  high strength steel/stainless steel  alternating overlapping  mechanical properties

摘要:

采用等离子弧增材系统实现了不锈钢/高强钢异质异构增材构件制备，等离子弧增材构件具有良好的沉积形貌及优异的力学性能.为揭示叠合方式对等离子弧异质增材构件的宏微观组织和力学性能特征影响，研究采用了体视显微镜、金相显微镜、拉伸及硬度等测试方法.结果表明，不锈钢/高强钢异质异构增材构件中存在两种过渡形式，即以奥氏体枝晶过渡和马氏体组织过渡.增材构件横截面硬度波动较大，主要是混合过渡区域的高合金元素导致的组织变化引起的.叠合方式的改变能够显著影响材料性能，在强度下降不多的情况下，提高材料的冲击韧性.

Abstract:

The plasma arc additive manufacturing process was used to realize the deposition of stainless steel/high strength steel with various composite structures. The components fabricated by plasma arc have good depositional morphology and excellent mechanical properties. In order to reveal the effect of the composite structures on the macro/microstructure and mechanical properties of the components, stereo microscope, metallographic microscope, tensile and hardness testing methods were used. The results show that there are two kinds of transition interface:laminated austenite-dendrite transition and martensite transition. The microhardness fluctuation in the cross section of the components were large, which is mainly caused by the change of the structure due to the alloy elements. The various composite structures can significantly affect the properties of materials, and "stainless steel+ high strength steel"alternating structure improves the impact toughness of materials when the strength decreases little.