經Cr元素添加後之Ni-19Si-(Nb,B)合金，利用抗拉試驗來探討其機械性質 之變化;並藉由X光繞射分析及掃描電子顯微鏡來檢測該合金的組織變化。研究結 果顯示該合金具有三種組織相，即α(fcc)相，β(L1��)相，及Nb�衹i�特i析出相。 當Cr的添加量超過1at時，將會急劇降低該合金的延性。另外，添加Cr的 Ni-19Si-3Nb-0.2B合金所表現的脆性破裂，推論其原因，可能是添加之Cr元素吸收 了部分B元素，因而降低了晶界的結合強度，導致脆性破裂。
The mechanical properties of Ni-19Si-(Nb, B) poly crystals alloyed with Cr were investigated by tensile tests. The microstructures change varied by the additions of Cr also examined by x-ray diffraction, scanning electron microscopy. The results reveal that there are three phases, α(fcc) and β(L1��)phase, and one precipitate phase of Nb�衹i�特i existing in the cast Ni-19Si-3Nb-0.2B-xCr alloys. The effect of Cr additions in these alloys will decrease their ductility sharply when the additions of Cr exceed1.0 at.. Additionally, the brittle fracture behavior of the Ni-19Si-3Nb-0.2B alloy with Cr additionis presumably to be the effect of Cr element which consumes some part of B element, and reduces the adhesion of grain boundary of the matrix, then results in a brittle fracture.
