摘要 |
<p>Provided is joint part capable of suppressing diffusion of carbon and nitrogen contained in the steel member to the TiAl-based alloy member and suppressing formation of voids, titanium carbide or a nitride due to diffusion of carbon and nitrogen contained in the steel member, and thereby suppressing decrease in the brazing strength. A joint part comprises a steel member containing alloy elements including C and Cr, a TiAl-based alloy member, and a Ni-based brazing filler metal via which the steel member and the TiAl-based alloy member are joined to each other, wherein the steel member has a carbide and a nitride each forming a bond with at least one of the alloy elements at least on a side of a boundary with the Ni-based brazing filler metal, and diffusion of C and N to the Ni-based brazing filler metal adjacent to the TiAl-based alloy member is suppressed by the carbide and the nitride. The joint part may be a turbine body 1 comprising a turbine wheel 2 and a shaft 3, and a structural steel material of the shaft 3 is structural steel material containing 0.30 to 0.45 wt% of C and 0.85 to 1.25 wt% of Cr, or a martensitic stainless steel material containing at most 15 wt% of C and 11.5 to 13 wt% of Cr.</p> |