Strength and Ductility Improvement through Thermomechanical Treatment of Wire-Feed Electron Beam Additive Manufactured Low Stacking Fault Energy (SFE) Aluminum Bronze

Abstract

An as-cast macrostructure of electron beam additively manufactured metallic materials was represented by coarse columnar grains whose axes were inclined at 25° with respect to the substrate’s plane. One part of the as-grown samples was annealed to form a coarse grain microstructure while the other part was pre-deformed by forging and then annealed what allowed obtaining recrystallized microstructures with small grains and multiple annealing twin boundaries. This sample showed both high strength and plasticity during the tensile tests. These tensile tests demonstrated also two-stage stress-strain curves as depended on their strain hardening rates. High and low strain hardening rates corresponded to a twinning-dominated deformation at stage II and dislocation-base deformation at stage III. A submicron size strain-induced grain-subgrain microstructure was formed in the vicinity of a necked zone as a result of combined twinning/dislocation grain refining.

Improvement in Wear Resistance Performance of CuAl8Fe3 Single-Phase Aluminum Bronze via Slide Diamond Burnishing

“…The positive effect of strain hardening, and in particular of severe plastic deformation for surface modification of bronze alloys, was demonstrated in (Ref [35][36][37][38]. Due to the high plasticity of the aCu-phase in CuAl8Fe3 bronze, structural changes in the surface layers are observed both in the specimens treated via DB and in the specimen treated only by fine turning.…”

Numerical Study and Experimental Validation of Deformation of <111> FCC CuAl Single Crystal Obtained by Additive Manufacturing

“…Under uniaxial loading, this orientation is characterized by Metals 2021, 11, 582 3 of 16 deformation on six equiloaded slip systems (three planes with two directions in each plane). An aluminum bronze sample was grown on an AISI 321 steel substrate from a Cu-7.5wt.%Al wire using an electron beam wire-feed machine designed and built at the Institute of Strength Physics and Material Science of Siberian Branch of Russian Academy of Sciences (ISPMS SB RAS) [1]. Single crystals with a required crystallographic orientation were cut from the ingots.…”

“…Progress in additive technologies has attracted even more attention to the role of classic substructural mechanisms of deformation and hardening of metal materials. This is concerned with the directional crystallization of grains and the formation of a so-called dendritic structure in the materials produced by additive manufacturing [1][2][3][4][5]. On one hand, large columnar grains deteriorate the mechanical properties of the materials.…”

“…Due to their high strength, excellent corrosion, and wear resistance, CuAl alloys have advantageous over other structural materials. Progress in powder 3D printing and the development of new technologies of wire-feed additive manufacturing [1,13,14] stimulate growing interest in this material. Moreover, the shape memory effect and thermomechanically induced structural transformations in CuAl based compounds make them new objects for the elaboration of a new class of adaptive structural materials [1,14].…”

Predicting the Strength of EBAM 3D Printed Ti-6Al-4V from Processing Conditions

“…The thermo-mechanical cycles and processing parameter variability that is intrinsic to AM printing, subsequently influence all aspects of the final part's material properties [9,15,16]. Variations in thermal experiences and processing conditions result in microstructural gradients, making the science of predicting the material properties and resulting residual stresses a complex multiphysics simulation problem.…”