Abstract Three nickel-based amorphous filler materials with composition of [B-Ni9-xCrx]BSiNi (x = 0,1,2) were designed to braze K4169 superalloy according to cluster-plus-glue-atom model. The microstructure of K4169 nickel- based alloy brazed joints was examined, and the shear strength of the joint was also measured via pressure-shear tests. The brazed seam consists of γ-Ni solid solution, Nb6Ni16Si7 and CrB phases of joint brazed with [B-Ni7Cr2]BSiNi filler. More Nb6Ni16Si7 phase formed in the brazed seam with more Cr addition in filler material, because Cr promoted the diffusion of Nb atoms from base material to brazed seam. Diffusion zone was composed of needle-like Cr-Mo rich borides and blocky MC carbides (NbC, TiC). The amount of Cr-Mo rich borides went up with the enhancement of Cr content in filler material. The shear strength of joint reached 689 MPa when brazed with [B-Ni9]BSiNi filler, followed by 562 MPa with [B-Ni8Cr1]BSiNi filler and 450 MPa with [B-Ni7Cr2]BSiNi filler. In addition, Cr-Mo rich borides and continuous precipitation (Nb6Ni16Si7 and CrB) exhibited low resistance to crack, resulting in the degradation of joint strength.

中文翻译：

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Ni基非晶填料中Cr含量对K4169镍基合金钎焊接头组织和剪切强度的影响

摘要 根据团簇加胶原子模型，设计了三种成分为[B-Ni9-xCrx]BSiNi (x = 0,1,2)的镍基非晶填充材料来钎焊K4169高温合金。研究了 K4169 镍基合金钎焊接头的微观结构，并通过压力剪切试验测量了接头的剪切强度。钎焊缝由γ-Ni固溶体、Nb6Ni16Si7和[B-Ni7Cr2]BSiNi填料钎焊接头的CrB相组成。在钎焊缝中形成更多的 Nb6Ni16Si7 相，在填充材料中添加更多的 Cr，因为 Cr 促进了 Nb 原子从母材向钎焊缝的扩散。扩散区由针状富铬钼硼化物和块状 MC 碳化物（NbC、TiC）组成。Cr-Mo富硼化物的量随着填充材料中Cr含量的增加而增加。[B-Ni9]BSiNi填料钎焊接头的剪切强度达到689 MPa，其次是[B-Ni8Cr1]BSiNi填料钎焊562 MPa和[B-Ni7Cr2]BSiNi填料450 MPa。此外，富含 Cr-Mo 的硼化物和连续析出（Nb6Ni16Si7 和 CrB）表现出低抗裂性，导致接头强度下降。