| 摘要 |
PURPOSE: To provide a wear resistant sintered alloy for valve seat and a method for manufacturing the same, wherein an abrasion amount of the sintered alloy is reduced as a whole by simultaneously performing sintering and copper infiltration on powder compact properly comprising Fe, Cr, Co, C, Mn, W and V and tempering the sintered and copper infiltrated alloy. CONSTITUTION: The wear resistant sintered alloy for valve seat comprises 100 wt.% of powder compact containing iron as a main component, 0.8 to 1.2 wt.% of carbon, 15.0 to 20.0 wt.% of chromium, 0.3 to 0.6 wt.% of manganese, 25.0 to 30.0 wt.% of cobalt, 5.0 to 7.0 wt.% of tungsten and 2.0 to 4.0 wt.% of vanadium; and 20 to 30 wt.% of copper for the powder compact. The method for manufacturing the wear resistant sintered alloy for valve seat comprises first step of blending iron powder as a main component with 0.8 to 1.2 wt.% of carbon powder, 15.0 to 20.0 wt.% of chromium powder, 0.3 to 0.6 wt.% of manganese powder, 25.0 to 30.0 wt.% of cobalt powder, 5.0 to 7.0 wt.% of tungsten powder and 2.0 to 4.0 wt.% of vanadium powder and press forming the blend by a surface pressure of 5 to 8 ton/cm¬2; second step of air cooling the sintered and copper infiltrated alloy after simultaneously sintering powder compact passing through the first step and infiltrating 20 to 30 wt.% of copper for 100 wt.% of the powder compact into the powder compact in a temperature range of 1,140 to 1,180 deg.C; and third step of tempering the air cooled alloy in a temperature range of 450 to 550 deg.C.
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