Processing optimisation, mechanical properties and microstructural evolution during selective laser melting of Cu-15Sn high-tin bronze

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:721

Article

Mao, Zhongfa¹  Zhang, David Z.^1,2  Jiang, Junjie¹  Fu, Guang¹  Zhang, Peng¹ 

[1] Chongqing Univ, State Key Lab Mech Transmiss, Chongqing 400044, Peoples R China

[2] Univ Exeter, Coll Engn Math & Phys Sci, North Pk Rd, Exeter EX4 4QF, Devon, England

关键词: Selective laser melting;    Copper alloys;    Microstructure;    Crystal growth;    Mechanical properties;   

DOI  :  10.1016/j.msea.2018.02.051

来源: Elsevier

【 摘 要 】

Selective laser melting (SLM), as a novel additive manufacturing technique, has attracted increasing attention in copper alloys. In this research, to investigate forming processing and attendant mechanical properties of high-tin bronze in SLM, a statistical relationship between processing parameters (laser power, scanning speed and hatch space) and density of Cu-15Sn bronze in SLM was established using an experimental approach with response surface method and analysis of variance. As such, nearly fully-dense SLM Cu-15Sn bronze specimens were firstly manufactured whose reasonable microstructural evolution and mechanical properties were investigated before and after annealing and compared with QSn15-1-1. (GB/T 5231-2012) drawing specimens. It is found that the SLM Cu-15Sn specimens present the significantly fine grain microstructures that consist of cellular and dendritic structures. The ultimate tensile strength varies from similar to 661 MPa to similar to 545 MPa, the elongation at break from 7.4% to > 20% and the Vickers hardness ranges from similar to 212 HV 0.3 to similar to 168 HV 0.3 for SLM Cu-15Sn specimens after annealing, which are generally superior to those of QSn15-1-1 specimens. In addition, it has been proposed that the dominated strengthening mechanism of SLM Cu-15Sn parts has transformed from fine-grain to solid solution strengthening after annealing.

【 授权许可】

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