Effect of Applied Temperature and Strain Rate on Laser Welded Stainless Steel Structures

Abstract

Sealed containers that hold organic substances can fail if organic material decomposition that occurs at elevated temperatures causes high enough pressures to cause a breach anywhere within the container or at welded or joined sections of the container. In this study, the response of stainless steel structures sealed by laser welding was of interest. Cylindrical can structures were constructed of two base materials, 304L stainless steel in tube and bar form, and joined by partial penetration laser welding. The base and weld materials contributed to the overall elastic–plastic response that led to failure in the weld region. The response of specimens constructed from sections of the cylindrical can structures was measured experimentally under thermomechanical loadings that investigated applied strain rate and temperatures (25–800 °C). Prior to testing, extensive measurements of the partial penetration weld geometry and cross section were completed on each specimen to enable correlation with measured response and failure. The experimental results of these sub-structure specimens tested at elevated temperatures are presented. Additionally, the material characterization results of the two 304L stainless steel materials used in constructing the cylindrical cans are presented.