材料期刊网

在NiFeCrWMoTiAl合金断口的萃取碳复型上,观察到:合金中的硼可以减少和消除能脆化合金晶界的Ti_4C_2S_2脆性薄片;硼含量为0.025—0.050％和0.075—0.100％时,M_3B_2分别呈薄片(或枝晶薄片)状和块状;在1200℃以下温度加热时,颗粒状M_3B_2沉淀,而且薄片状M_3B_2向颗粒状M_3B_2转变。

An electron microscope study was made of the effect of B, especially as M_3B_2, on a NiFeCrWMoTiAl alloy using the fractograph of extraction carbon replica. The B additive may decrease and dissipate the, brittle flakes of Ti_4C_2S_2 which ordinarily embrittle the alloy without any B along the grain boundaries. The M_3B_2 was observed in the shape of flakes or dendritic flakes and of blocks in the alloys containing 0.025—0.050 and 0.075—0.100% B respectively. During heating under temperature below 1200℃, the M_3B_2 grains precipitate and the flaky M_3B_2 transforms into grains as well.