The inter-granular penetration inside CoCrMnFeNi high-entropy alloy (HEA) in the dissimilar brazing joint of 304 stainless steel and this HEA were regulated for the first time by using Ag72Cu as filler metal (FM) and by annealing HEA. The as-rolled HEAs were annealed at a series of temperatures for 1 h before brazing. The microstructural evolution of the dissimilar joints found that penetration was reduced with increasing annealing temperature because of the consistent decreases in grain boundary density, which reduces the channels for penetration, and the gradually stable grain boundaries in HEA, which decreases the driving force of inter-granular penetration. The direct inter-diffusion between the HEA grain and FM was limited. HEA atoms in FM originated from the dissolved HEA during brazing, manifesting the acceleration of penetration on the inter-diffusion between HEA and FM. Regulating inter-granular penetration in the dissimilar joint decreased the stress concentration at the HEA side and ensured the solution-strengthening effect of Mn in FM and the contact area between FM and HEA. The tensile strength of the dissimilar joint with regulated inter-granular penetration could reach 514.98 MPa and is considerably higher than that of the joint with few penetration, which hints that penetration does not always impair the mechanical performance of joints.

首次以Ag72Cu为填充金属（FM）并通过对HEA进行退火，来调节304不锈钢和该HEA异种钎焊接头中CoCrMnFeNi高熵合金（HEA）内部的晶粒间渗透。在钎焊之前，将轧制的HEA在一系列温度下退火1小时。异种接头的微观结构演变发现，由于晶界密度的持续降低（这会减少渗透的通道）以及HEA中逐渐稳定的晶界（这降低了晶间驱动力），随着退火温度的升高，渗透率会降低。颗粒渗透。HEA颗粒和FM之间的直接相互扩散受到限制。FM中的HEA原子源自钎焊过程中溶解的HEA，在HEA和FM之间的相互扩散中表现出渗透的加速。调节异种关节中的颗粒间渗透降低了HEA侧的应力集中，并确保了Mn在FM中的固溶强化作用以及FM与HEA之间的接触面积。具有规则的晶间渗透的异种接头的抗拉强度可以达到514.98 MPa，大大高于几乎没有渗透的接头的抗拉强度，这表明渗透并不总是会损害接头的机械性能。