Study the effect of thermal cycling of brazing and post-brazing processes on Cu-Ni alloy

• Published in: Materials today : proceedings Vol. 27; pp. 2626 - 2630
• Main Authors: Shaji, Shanil, Santhosh kumar, R., Thomas Tharian, K., Amruth, M., Manimaran, A., Babu, Jalumedi
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.01.2020
• Subjects: Aging; Brazing; LRE; Material properties; Pre-burner; Thermal cycling; Aging; Brazing; Pre-burner; Thermal cycling; LRE; Material properties
• ISSN: 2214-7853; 2214-7853
• DOI: 10.1016/j.matpr.2019.11.079

Analysis of thermal cycling effects of brazing and post-brazing processes is important, which affects the mechanical and metallurgical properties of materials in Standard Heat Treatment condition. The material used for present study is Copper-Nickel alloy, which is to be jointed with Precipitation hardenable (PH) stainless steel. These materials are used in the parts of pre-burner of the Liquid Rocket Engine (LRE). Hardness and microstructure of Cu-Ni alloy was analyzed in Extruded Condition (EC), Brazing Condition (BC) and Post-Braze Condition (PBC). Brazing thermal cycle is done from room temperature (RT) to a temperature of 910 °C with preheating at 500 °C, 600 °C, 700 °C, 850 °C and soaked at 910 °C for 15 min, then furnace cool to 850 °C, after that air cool to room temperature (RT). Post brazing thermal cycle is done at 500 °C for 2hrs to achieve desired properties in base materials and PH stainless steel. Microstructure, mechanical properties at −196 °C, RT, 250 °C, 450 °C & 650 °C were evaluated in PBC, which is essential for design & operation of LRE. Additional Field Emission Scanning Electron Microscope (FE-SEM) investigations prepared with EDS (X-Ray Energy Dispersion Spectrometer) results are used to analyse the fractural failures in detail. The present work discusses about the significant influence of thermal cycling effects on base material properties of brazing and post brazing processes.