Diffusion Bonding 321-Grade Stainless Steel: Failure and Multimodal Characterization.

Vacuum diffusion-bonded printed circuit heat exchangers are an attractive choice for the high-temperature, high-pressure demands of next-generation energy applications. However, early reports show that the high-temperature materials desired for these applications suffer from poor bond strengths due to precipitation at the bond line, preventing grain boundary migration. In this study, a diffusion bond of the high-temperature stainless steel grade 321H is investigated, and poor mechanical properties are found to be caused by Ti(C, N) precipitation at the bond line.

Characterisation of worn WC tool using STEM-EDS aided by principal component analysis.

Interdiffusion and chemical reactions contribute to tool wear in metal machining. Increased understanding of these processes, through characterisation of worn tools, can facilitate design of more resilient materials through chemical and diffusional passivation. However, the unknown reaction conditions, the large number of elements, and the formation of interspersed phases makes for a complex analysis.