The Impact of Plastic Deformation on the Microstructure and Tensile Strength of Haynes 282 Nickel Superalloy Produced by DMLS and Casting

Abstract

The article presents the results of research on the influence of plastic deformation on the microstructure and tensile strength of Haynes 282 nickel superalloy produced by direct metal laser sintering (DMLS) and a conventional technique (casting). Samples were tested for dimensional accuracy using a 3D scanner. Then, the samples were subjected to plastic deformation by rolling. The microstructures of the DMLS and the as-cast samples were analysed using a scanning electron microscope. The strength properties of the samples were determined in a static tensile test. Microhardness measurements of the samples were also performed. Based on the analysis of the dimensional accuracy, it was found that the surface quality of the components produced by DMLS is dependent on the input parameters of the 3D printing process. Using the DMLS method, it is possible to produce Haynes 282 with a fine-crystalline microstructure containing dendrites. The fine-crystalline dendritic microstructure and low porosity showed very good tensile strength compared to the as-cast material. It was also found that the increase in the degree of plastic deformation of the as-cast Haynes 282 and the samples produced by the DMLS technique resulted in an increase in the strength of the tested samples, with reduced ductility.

Thermal Stability and Mechanical Behavior of Ultrafine-Grained Titanium with Different Impurity Content

“…Tensile tests were conducted at an initial strain rate of 10 −3 s −1 using a Zwick/Roell Z005 (Zwick GmbH & Co. KG, Ulm, Germany) testing machine equipped with a 1 kN load cell. Digital image correlation (DIC) system was used for strain measurements which has been described more in detail in [ 27 , 28 ]. Based on the obtained stress–strain curves, the strain-hardening rate Θ was calculated as Θ = dσ/dε where σ and ε are a true stress and true strain, respectively.…”

Effects of aluminised-coating on microstructure and properties of Ni–Co-base superalloys

“…Sarraf et al 10 discussed a three-stage coating formation mechanism during reactive air aluminising in a Ni-base superalloy, and the aluminide coating of pack cementation was decided by the aluminium activity, especially the aluminising temperature and time. 11 The low-activity aluminide coating deposited at high temperatures always possessed a thick double-layered structure, 12 whilst a low depositing temperature of high activity resulted in a triple-layered coating structure in which a middle layer consisting of β-NiAl phase without precipitates due to the inward diffusion of Al. 13 Yener et al 14 demonstrated that the macroscopic layer thickness of the IN738 alloy was significantly increased with increasing temperature owing to a higher diffusion rate.…”

Influence of Ion Nitriding on Microstructure and Properties of Haynes 282 Nickel Superalloy Specimens Produced Using DMLS Technique

“…Laser Beam Powder Bed Fusion manufacturing techniques (LB-PBF), for example, Selective Laser Melting (SLM) or Direct Metal Laser Sintering (DMLS), are increasingly used in the producing of metallic parts from various alloys, such as Ni-based superalloys, stainless steels or titanium materials [ 13 , 14 , 15 , 16 , 17 , 18 , 19 ]. These processes in which layer after layer of metal powder are selectively melted by the interaction of a high energy density laser beam offer many advantages over conventional manufacturing methods.…”

“…The negative effects are mainly caused by the crystallographic texture, the structure of melt pools, the privileged distribution of certain phases and carbides, and the presence of asymmetrical defects [ 19 , 20 ]. Boswell et al in their study [ 20 ] showed that the anisotropic effect could be effectively reduced with appropriate dissolution and ageing heat treatment, leading to recrystallization and local texture reduction.…”