Identifier

etd-011218-224945

Abstract

The heat-treating industry is in need of heat- treatment furnace materials and fixtures that have a long service life and reduced heat capacity. Based on microstructural analysis of components that were used until failure in carburization furnace application, it was found that the primary reason for failure was the excessive carburization that leads to “metal dustingâ€� and subsequent cracking. Aluminizing is widely used to increase the high temperature oxidation and carburization resistance of nickel- based alloys. In this dissertation, RA330, RA602CA, 304L/316L, Inconel 625 alloys were selected to study their performance in an industrial carburization furnace for times up to two years. These alloys were exposed in both the as-fabricated and aluminized condition. The test samples were exposed to Cp=0.7-1.3% carburizing atmosphere at approximately 900℃ for 3 months, 6months, 12months, 18 months and 24months. The oxidation properties and oxide stability at high temperatures will be presented. In addition, the analysis of microstructural development during long term exposure experiments in an industrial carburizing furnace will be presented. These samples were characterized using optical and scanning electron microscope, EBSD, and x-ray diffraction. It was found that the aluminized alloys exhibited lower weight gain and carbon uptakes.

Publisher

Worcester Polytechnic Institute

Degree Name

PhD

Department

Materials Science & Engineering

Project Type

Dissertation

Date Accepted

2018-01-12

Accessibility

Unrestricted

Subjects

superalloys, aluminizing, inter-metallics, carburi

Share

COinS