Fractographic Analysis of CVD (Chemically Vapor Deposited) ZnS (Zinc Sulfide)
Abstract
Chemically vapor deposited (CVD) zinc sulfide is used as an infrared transmitting window on heat-seeking missiles and laser systems. In many of these in-service environments, mechanical and thermal stresses can lead to crack growth and fracture. Thus, a knowledge of the mechanical and thermal properties of these materials is necessary. Although many investigations and research papers have concentrated on the processing and properties of ZnS material, very little has been written on the characterization of the fracture surface of ZnS. This report is written to demonstrate the techniques of determining the fracture origin and the surrounding topography. The fracture toughness, or resistance to crack propagation, is determined from fracture surface features. Their values compare well with reported values. More importantly, observation of the fracture surface provides a tool by which we can determine the state of stress, identify the fracture origin, and analyze the fracture process.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 11, 1988
- Accession Number
- ADA197394
Entities
People
- J. J. Mecholsky
- P. L. Yoder
Organizations
- Pennsylvania State University