EFFECT OF STRUT THICKNESS ON ROOM AND HIGH TEMPERATURE COMPRESSIVE PROPERTIES OF BLOCK-TYPE Ni-Cr-Al POWDER POROUS METALS

摘要

This study investigated the effect of strut thickness on the room and high temperature compressive properties of block-type Ni-Cr-Al powder porous metals with similar to 3000 mu m pore size manufactured using a new powder process. Two block-type Ni-Cr-Al porous metals with different strut thicknesses were manufactured. The strut thicknesses of two block foams were 340 mu m (A) and 383 mu m (B), respectively. Room temperature, 500 degrees C, 650 degrees C and 800 degrees C compressive tests were performed. The compressive results identified typical elastic, plateau and densification regions of foam material in all temperature conditions. Regardless of the strut thickness, compressive strength (maximum peak stress) decreased as deformation temperature increased. In all deformation temperature ranges, the compressive strength measured higher in the porous metal with greater strut thickness (B). The high temperature deformation behavior of powder porous metal was confirmed to be affected by the structural factor and microstructural factor of the porous metal. With the findings described above, this study also discussed the high temperature deformation mechanism of the Ni-Cr-Al metal foam based on fracture surfaces after the high temperature compressions.