Causes Of Severe Deformation Of Stainless Steel Mesh Belts In Sintering Furnaces

Severe deformation of stainless steel mesh belts for sintering furnaces mainly stems from thermal, mechanical and material‑related factors.

Thermal Factors

Over‑temperature operation alters material properties of mesh belts once furnace temperature exceeds their rated temperature resistance. For 304 stainless steel mesh belts, the typical long‑term operating temperature is around 870 °C. Sustained over‑temperature triggers grain growth, reduces material strength and brings about deformation. Proper selection of stainless steel grades is critical to minimize thermal deformation.

Uneven temperature distribution is another major cause. In large continuous sintering furnaces, uneven heating elements or inconsistent thermal insulation create significant temperature gradients. As the mesh belt travels through hot and cold zones, differential thermal expansion generates internal stress across the integral belt structure. Deformation such as local bending or twisting occurs when internal stress surpasses the material yield strength. Regular inspection of mesh belt conditions helps diagnose defects of furnace bodies.

Mechanical Factors

Excessive tension takes place during installation and commissioning. Operators may over‑tighten the belt for better meshing between mesh belt and driving pulleys. Subjected to combined high temperature and workpiece load, over‑stretched belts deform readily. Excessive tension also accelerates wear at belt joints and undermines operational stability. Strict SOPs for installation and commissioning are required to avoid assembly errors.

Uneven loading arises from asymmetrical placement of parts. In powder metallurgy sintering, unevenly stacked powder compacts impose one‑sided loads. Heavily‑loaded sections sink gradually and produce permanent deformation. Operator training should stress uniform workpiece layout.

Abnormal friction between mesh belt and internal components (furnace walls, support rollers) accumulates localized stress. Worn roller surfaces or misaligned contact angles induce unbalanced friction forces, which build up over long‑time service and result in severe deformation. Scheduled inspection routines are essential for smooth belt operation.

Material‑related Factors

High‑temperature chemical reactions between workpieces and mesh belts contribute to failure. Metallic compacts may undergo alloying reactions with stainless steel, forming surface compounds that harden or embrittle local areas. Corrosive gases released during sintering attack the substrate and lower mechanical strength. A typical example is copper brazing furnaces: contact with molten copper corrodes stainless steel mesh belts and aggravates deformation over time.