Experimental Research And Property Analyses On DLMS Of FGH95 Nickel-based Alloy Powder

Direct Laser Metal Sintering (DLMS) is a kind of advanced manufacturing technique to manufacture metal parts directly. In this paper, the direct metal laser sintering (DMLS) experiment with the FGH95 Nickle-based alloy power was performed. The mechanical property of specimens was tested, and the changes of them were analyzed along with the different technology parameters.The main works are as following:(1) A series of based experiments with DLMS for FGH95 were carried out, and the typical parameters of DLMS for FGH95 have been obtained with the laser power of 800W～900W and the scan speed of 1.0m/min～1.2m/min. The well macroscopical quality and the compact microstructure of the specimens prepared with the typical parameters is observed. The microstructure of the specimens is composed mainly of equal-axes crystale and cylindrical crystale.(2) The largest value of the tensile strength of specimen is in excess of 700Mpa, closed to that of specimens prepared by powder metallurgy technology. The plastic fracture was observed at the breakpoint. With the increasing of laser power, the tensile strength is put up a increasing trend. There is not apparent rule that the scan speed effected on the tensile strength. The value of tensile strength is approach to 720 Mpa when the scan speed is 1.0 m/min.(3) The value of microhardness varies between 400～600 HV with the different laser power and scan speed. The distribution of microhardness value is different with the different parameters. The maximum value of 592HV was gotten with the laser power of 1100W.(4) The mechanism of the defects in specimen, including balling,cavity,crack,and so on, was analyzed in a nutshell, and the the measures to prevent those defects were discussed.