PLASMA-JET COATING OF TUNGSTEN ON STEEL
Abstract
Three methods for bonding plasma-jet sprayed tungsten to steel were developed and evaluated in an approach to the problem of providing heat- resistant materials for the design and fabrication of components for high temperature applications. Three types of coating were sprayed by plasma-jet on 1020 steel substrates: (1) an all tungsten coating, (2) a coating graded from 1020 steel at the interface to tungsten at the outer surface, and (3) a coating graded from iron at the interface to tungsten at the outer surface. By the latter two coating methods, a less severe thermal expansion gradient was developed between the substrate and the coating. Pre-heating the substrates increased the fusion bond at the interface. Post-heat treatments eliminated residual stresses within the coating and promoted grain growth and diffusion across the fusion zone. The tungsten-iron graded coating on the 1020 steel substrate displayed excellent resistance to shock and withstood high temperature corrosion conditions 2 1/2 times longer than uncoated substrates. The investigation emphasized the potential of the plasma-jet gun in providing a means for depositing a protective coating on a metallic substrate.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 30, 1962
- Accession Number
- AD0625800
Entities
People
- Daniel J. Murphy
- Richard L. Landingham
- Robert A. Damon
Organizations
- University of Arizona