Effects of Alloying Elements on Embrittlement of 15Cr-26Ni-1.25Mo Type Precipitation Hardening Alloy
1985 Volume 71 Issue 1 Pages 107-113
Details
1985 Volume 71 Issue 1 Pages 107-113
The object of this study is to characterize the effect of alloying elements on the toughness of 15Cr-26Ni-1.25Mo type alloy steels (A286) aged at 650°C.
The results obtained are summerized as follows.
(1) The Charpy absorbed energy of 15Cr-26Ni-1.25Mo type alloy steels aged at 650°C was decreased with increasing C content. This fact suggestes that aging embrittlement closely depended on C content.
(2) Precipitates were found on the grain-boundaries of the alloys aged at 650°C for 1 500h. Microscopic examination indicated that these precipitates grew as aging time increased. Auger electron spectroscopy showed that titanium carbides were included in the precipitates.
(3) Decreases of C to 0.03wt% and Ti to 1.65wt% were beneficial in keeping good Charpy absorbed energy the value of 35 to 55 N-m in the specimens aged for 6 000h at 650°C, without reduction of creep rupture strength at 650°C.
