Study On The Rapid Preparation Process And Performance Of 304 Combined Sintering Stainless Steel Wire Mesh

Combined sintering stainless steel wire mesh is a kind of porous materials sintered by stainless steel punched plate and stainless steel meshes which have different aperture. It has the properties of fine thermal conductivity, electrical conductivity, ductility and toughness, fine weldability and well processing characteristics. By controlling porosity, aperture and the distribution of aperture, the combined sintering wire mesh has various properties, which make it widely used in the fields of filtration and separation, noise elimination, shock-absorbing, heat exchange and catalytic agent carrier, and so forth. Stainless steel wire mesh is produced by solid state sintering in industry. Solid state sintering based on diffusion bonding, demands strict surface treatment and long holding time at high temperature. So the solid state sintering method has some shortages, such as high manufacturing cost, poor bonding strength and production embrittlement. In this paper, 304 combined sintering stainless steel wire mesh was prepared by TLP and brazing at relatively low temperature. The microstructure, mechanical property, corrosion resistance and failure form of the combined stainless steel wire mesh prepared by three methods were studied.Using Cu-P alloy powder as interlayer, 304 combined stainless steel wire mesh was brazed at 910~950℃(30 min, 1 MPa). The joints between punched plate and mesh consisted of Cu(Fe,Cr) solid solution in middle zone and phosphide in diffusion zone. Due to the raising temperature, the middle zone became narrower and the diffusion zone became wider. What’s more, the joint became uniform at 960℃(30 min, 1 MPa) except little interlayer in the fillet zone. 90°bending test showed that 304 combined stainless steel wire mesh prepared by TLP(910℃, 960℃) had stronger bending strength than that prepared by solid state sintering. The failure form of TLP combined wire mesh was wire fracture, and the failure form of solid state sintering combined wire mesh was welded joint break. All kinds of combined wire mesh had increasing weight loss rate with time increasing in 5% NaCl solution and 15% HCl solution. 960℃ TLP combined wire mesh had the lowest rate, followed by solid state sintering combined wire mesh, followed by 910℃ TLP combined wire mesh. 90°bending test showed that 304 combined stainless steel wire mesh prepared by 960℃ TLP had the lest welding joint break after corrosion, followed by 910℃ TLP combined wire mesh, followed by solid state sintering combined wire mesh.Using BNi-2 brazing filler metal as interlayer, 304 combined stainless steel wire mesh was brazed under the pressure of 0.5 MPa, 1.5 MPa, 2.0 MPa(1 030℃, 10 min). The cloud form intermetallic compounds in the middle zone disappeared when pressure rose from 0.5 MPa to 1.5 MPa. 90°bending test showed that the major failure form of 304 combined stainless steel wire mesh brazed under the pressure of 0.5 MPa was welded joint break. However, when the pressure was 1.5 MPa or 2.0 MPa, the major failure was wire fracture. All kinds of combined wire meshes had increasing weight loss rate with time increasing in both 5% NaCl solution and 15% HCl solution. 960℃ TLP combined wire mesh had the lowest weight loss rate, followed by solid state sintering combined wire mesh, followed by 910℃ TLP combined wire mesh. 90°bending test showed that 304 combined stainless steel wire mesh prepared by 960℃ TLP had the lest welding joint break after corrosion, followed by 910℃ TLP combined wire mesh, followed by solid state sintering combined wire mesh.The weight loss rate of combined wire mesh brazed under the pressure of 0.5 MPa and 1.5 MPa in 5% NaCl solution and 15% HCl solution was investigated 1.5 MPa combined wire mesh not only had the lowest wight loss rate, but also had the least welded joint break rate than TLP and solid state sintering combined wire mesh. In the 15% HCl solution, brazing combined wire meshes showed mainly uniform corrosion. Solid state sintering combined wire mesh, by contrast, showed mainly perforation corrosion in part. CoMPared with solid state sintering combined wire mesh, 1.5 MPa combined wire meshes had better intergranular corrosion resistance performance, and had no abnormal growth phenomenon of crystal.