摘要
One of the challenges for bimetal manufacturing is the joining process.Hence,transient liquid phase(TLP)bonding was performed between 304L stainless steel and Cp-Ti using an Ag-Cu interlayer with a thickness of 75μm for bonding time of 20,40,60,and 90 min.The bonding temperature of 860℃ was considered,which is under the β transus temperature of Cp-Ti.During TLP bonding,various intermetallic compounds(IMCs),including Ti_(5)Cr_(7)Fe_(17),(Cr,Fe)_(2)Ti,Ti(Cu,Fe),Ti_(2)(Cu,Ag),and Ti_(2)Cu from 304L toward Cp-Ti formed in the joint.Also,on the one side,with the increase in time,further diffusion of elements decreases the blocky IMCs such as Ti_(5)Cr_(7)Fe_(17),(Cr,Fe)_(2)Ti,Ti(Cu,Fe)in the 304L diffusion-affected zone(DAZ)and reaction zone,and on the other side,Ti_(2)(Cu,Ag)IMC transformed into fine morphology toward Cp-Ti DAZ.The microhardness test also demonstrated that the(Cr,Fe)_(2)Ti+Ti_(5)Cr_(7)Fe_(17) IMCs in the DAZ on the side of 304L have a hardness value of HV 564,making it the hardest phase.The maximum and minimum shear strength values are equal to 78.84 and 29.0 MPa,respectively.The cleavage pattern dominated fracture surfaces due to the formation of brittle phases in dissimilar joints.
双金属制造面临的挑战之一是连接过程。因此,在860℃的结合温度,即Cp-Ti的β相变温度,采用厚度为75μm的Ag-Cu夹层,对304L不锈钢和Cp-Ti进行瞬态液相(TLP)结合,结合时间分别为20、40、60和90 min。在瞬态液相结合过程中,金属间化合物,包括Ti_(5)Cr_(7)Fe_(17),(Cr,Fe)_(2)Ti,Ti(Cu,Fe),Ti_(2)(Cu,Ag),以及Ti_(2)Cu,从304L不锈钢向Cp-Ti侧形成。一方面,随着时间的延长,元素的进一步扩散减少了304L不锈钢侧扩散影响区和反应区的Ti_(5)Cr_(7)Fe_(17),(Cr,Fe)_(2)Ti,Ti(Cu,Fe);另一方面,Ti_(2)(Cu,Ag)在Cp-Ti侧扩散影响区转变为精细形态。显微硬度试验表明,304L不锈钢侧扩散影响区的(Cr,Fe)_(2)Ti+TiTi_(5)Cr_(7)Fe_(17)是最硬相,硬度为HV564。最大剪强度和最小剪强度分别为78.84和29.0 MPa。由于不同节理中脆性相的形成,解理模式以断裂面为主。
