| Joining of cemented titanium carbide (or cermet) to 304 stainless steel using three types of low-Ag content brazing alloy was made by torch heating and in Ar-atmosphere furnace. Variation of interfacial structure and joining strength with brazing alloy and process was investigated. Joining strength was determined by fracture shear loading and high shear strength value up to 257 ㎫ were obtained for the joints brazed with BCZA-Si alloy. The strong bonding is attributable to the formation of plate-like Fe-Co-Ni alloy product at the cemented TiC/brazing alloy interface, which composed of 58.6 %Fe, 19.2%Co, 11.2%Ni, 3.4%Cu, 2.6%Ti, 1.6%Si and 1.3%Cr. That alloy product is formed by the solid-solution reaction between binder components(Co & Ni) in cemented TiC and components(Fe, Ni & Cr) deposited/desolved from stainless steel. For the use of BCZC-A10 alloy, Cr-carbide and high Cr-content Fe-Cr alloy product was continuously formed at the cemented TiC/brazing alloy interface. That Cr-carbide caused to deteriorate the joining strength of joints brazed with BCZC-A10 alloys. |
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