Hot isostatic pressing (HIP) technology can be used to fabricate complex parts with high-performance

however

there are some problems with this technology

such as the difficulty of manufacturing capsule for complex parts and the interface diffusion between heterogeneous capsule and powder

which will harm the performance. For this reason

a study on the selective laser melting (SLM)/HIP hybrid forming process was investigated. XRD

SEM

EBSD and tensile test were used to characterize the matrix / interface microstructure and tensile properties of the hybrid forming process. The results show that there are obvious pores and micro cracks in the matrix of Inconel 718 alloy directly formed by SLM

and the density is 98.3%. After HIP process

the Inconel 718 alloy matrix does not have obvious pores and cracks

but there is obvious prior particle boundary (PPB). Under the hybrid process conditions

the pores and cracks of the Inconel 718 formed by SLM are reduced

the characteristics of the melting track on the X–Y surface disappear

and the degree of anisotropy is reduced. After HIP

there is no obvious diffusion layer between the powder particle and the SLM-formed Inconel 718

and the interface is composed of fine grains with a thickness of about 16.7μm. The 650℃ high temperature strength of the interface is 626MPa. The tensile fracture surface is flat along the SLM and HIP state bonding interface. After solid solution + aging heat treatment

the interface bonding strength is increased to 990MPa

and the fracture is distributed in the SLM forming part. By analyzing the evolution of microstructure and properties

the feasibility of using the hybrid forming process to prepare complex parts is verified.