The effects of time on low frequency induction sintering of ferrous P/M materials

In this study, the effects of sintering time on mechanical properties of powder metal materials which sintered with low frequency were investigated. Hogenas ASC 100.29 iron powder (%3 Cu, %0,5 Graphite and %1 kenolube lubricant by weight) was used. Metal powder was pressed under 600 N/mm2 and 10X10X55 mm samples were formed.Samples were sintered with electric resistance furnace for 30 minutes and with induction sintering for 8,33, 15 and 30 minutes at 11200C to compare. Induction sintering was applied in %10H2 %90N2 atmosphere to protect samples from the negative effect of air.Dimension, weight and surface roughness measurement was applied to samples before and after sintering. Maximum stress and maximum strain of sintered samples are determined by three point bending test. Microhardness and microstructre of sintered samples were determined.It is defined that maximum stress and maximum strain of 8,33 minutes sintered samples with induction were higher than 30 minutes classical sintered samples with furnace and by increase of time, these values were increased. It was seen that with increasing time, copper melted better between and around iron powder.Developed induction sintering mechanism enables mass production sintering of powder metal samples.