Abstract
For additive manufactured aluminum alloys,the inferior mechanical properties along the building direc-tion have been a serious weakness.In this study,an optimized heat treatment was developed as a simple and effective solution.The effects of direct aging on microstructure and mechanical properties along the building direction of AISi10Mg samples produced via selective laser melting(SLM)were investigated.The results showed that,compared with the conventional heat treatment at elevated temperatures,direct aging at temperatures of 130-190℃could retain the fine grain microstructure of SLM samples and pro-mote further precipitation of Si phase,however,the growth of pores occurred during direct aging.With increasing aging temperature,while finer cell structures were obtained,more and larger pores were de-veloped,resulting in decreased density of the samples.Two types of pore formation mechanisms were identified.Considering the balance between the refinement of cell structure and the growth of pores,aging at 130℃was determined as the optimized heat treatment for SLM AISi10Mg samples.The tensile strength along the building direction of the 130℃aged sample was increased from 403 MPa to 451 MPa,with relatively high elongation of 6.5％.
基金项目
This work was financially supported by the National Key R&D Program of China(2017YFB0703104)
NETL
NSTL
维普
万方数据