Open AccessEffect of Temperature Field on Mechanical Properties of Direct Laser Deposited Ti-6Al-4V Alloy
Author(s) -
Marina Gushchina,
S. Yu. Ivanov,
Artur Vildanov
Publication year - 2020
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/969/1/012103
Subject(s) - materials science , dwell time , thermal conduction , deposition (geology) , alloy , metastability , titanium alloy , phase (matter) , field (mathematics) , pulsed laser deposition , non equilibrium thermodynamics , metallurgy , laser , elongation , composite material , thermodynamics , optics , thin film , ultimate tensile strength , nanotechnology , mathematics , chemistry , biology , paleontology , quantum mechanics , medicine , clinical psychology , physics , organic chemistry , sediment , pure mathematics
The mechanical and service properties of Ti-6Al-4V alloy parts produced by direct laser deposition (DLD) depend on the thermal cycle parameters. The temperature field during deposition is significantly affected not only by the parameters of the process, but also by the interpass dwell time and length of the deposited layers. The aim of the article is to establish the relationship between mechanical properties of deposited Ti-6Al-4V samples and DLD thermal cycle parameters. Numerical simulation was used in order to establish relationship between temperature field parameter and the process parameters. The nonlinear three-dimensional heat conduction problem was solved by the finite element method. It is shown that an increase in the dwell time between passes from 5 to 10 seconds leads to a significant decrease in the inter-pass temperature and an increase in the cooling rate. This leads to the metastable structure formation of the deposited layers of Ti-6Al-4V that consists mainly of a nonequilibrium a’-phase which hardness is higher than 390 HV. Without dwell time an equilibrium a + (3 structure with hardness of 360 HV and higher elongation is formed.