Effect of Laser Heat Treatment on the Microstructure and Properties of Alloy 800H

Wei Zhang,Liqiang Liu,Tao Jiang,Jing Li

doi:10.3390/met9030379

Abstract

The effects of laser heat treatment on the microstructure and properties of alloy 800H were investigated. The fracture morphology, elemental changes, and phase composition of the specimens were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-ray diffractometry (XRD). The results show that the long-lasting life of the specimen after laser heat treatment increased by 28.6%, and the elongation after fracture increased by 20.7%. The macroscopic morphology of the fracture specimen exhibited obvious ductile fracture morphology, and the changes in the elemental content and grain size significantly affected the ductility and toughness of the alloy. This study has certain guiding significance for the optimization of the heat treatment process of this type of alloy.

Highlights

Alloy 800H is a typical austenitic heat-resistant iron–nickel-based alloy with a high temperature creep resistance and good mechanical properties
It was found that laser heat treatment had obvious influence on the microstructure and properties of alloy 800H
The specific impact results are as follows: (1) The long-lasting life of the laser heat-treated samples increased by 28.6%, and the elongation after the break increased by 20.7%

Summary

Introduction

Alloy 800H is a typical austenitic heat-resistant iron–nickel-based alloy with a high temperature creep resistance and good mechanical properties. It is widely used in petrochemical pipelines, heat transfer tubes of steam generators, and industrial furnace pipes with their accessories [1]. Most of them have been based on the solid solution treatment, which controls the grain size of the alloy and improves its mechanical properties [2,3,4,5]. Gong et al [6] considered that the solution temperature has a significant effect on the mechanical properties of the alloy at room temperature and its grain size, the effect of holding time is not obvious, and the increase in temperature mainly affects its plasticity. Huang et al [7]

Methods

Results

Conclusion