| 摘要 |
<p>PURPOSE:To obtain sintered parts with which a substantial shrinkage fit effect is obtd. from the large shrinkage arising on the recess side in the stage of sintering by coupling compression moldings consisting of ground powder of cast iron and having recessed and the other metallic green compacts having projecting parts to each other and sintering the same. CONSTITUTION:For example, a sintered part 1 is formed of four divided parts A-D which are separately formed by compression molding of metallic powder and are coupled to each other prior to sintering then the coupled parts are sintered. Ground powder of cast iron is used for the metallic powder constituting the devided part A having a recess 4 and the part B is constituted of, for example, iron powder contg. copper powder. The recess 4 and a projecting part 5 are fitted to each other and both parts A, B are sintered at about 1,150 deg.C then both parts shrink and expand respectively to form a sintered body and a sintered part 1 united to one body is obtd. If a recess 6 and a projecting part 7 are used to couple the parts B and C, a material to expand more than B is required for the part C but if the directions of the recess and projection is reversed as shown by a dotted line 7', the constitution of the part C with the same ground powder of the cast iron as the powder of A is possible.</p> |
