Open AccessExperimental Research on The Distribution Law and Formation Reasons of As-cast Magnesium Alloy Laser Welding Porosity
Author(s) -
Shen Yanjin,
Jing Zhou,
Qian Liu,
Fangrong Wu
Publication year - 2020
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1605/1/012116
Subject(s) - porosity , welding , materials science , alloy , metallurgy , magnesium , magnesium alloy , composite material
Characteristics and distribution of the weld porosity are observed by using OM and SEM after as-cast magnesium alloy AZ91D is welded by CO2 laser. And then the formation model of two types of porosity is established by use of organization composition and distribution of metal base. Besides, the mechanism of pores in welding is explained on three aspects including microscopic porosity, macroscopic porosity and escape of bubbles. Based on these models and mechanisms, the shape characteristics and distribution of a welding porosity in a welding seam is explained and the formula of bubbles escape is also given. In addition, the measures to prevent welding porosity are discussed preliminarily. And based on the preliminary research on this topic, when (0.2%Ca+0.4%Y) is added to AZ910D magnesium alloy and high strain rolling is used, the laser weld porosity ratio of magnesium alloy can be effectively reduced.