JP2004524449A5 - - Google Patents

Claims (10)

A powder composition for warm molding comprising iron-based powder and lubricant powder, wherein the lubricant consists essentially of an amide represented by the following chemical formula:
DC _ma -BABC _mb -D
in this case,
D is -H, COR, CNHR, where R is a linear or branched aliphatic or aromatic group containing 2 to 21 carbon atoms,
C is, -NH (CH _{2) n} CO- group,
B is amino or carbonyl,
A is alkylene having 4 to 16 carbon atoms, optionally containing up to 4 oxygen atoms,
ma is an integer from 1 to 10,
mb is an integer from 1 to 10,
n is a powder composition which is an integer of 5 to 11. D is for COR, and where R is an aliphatic group having 16 to 20 carbon atoms, C is -NH (CH _{2) n} CO- and, in this case n is 5 or 11; B is amino; A is alkylene having 6 to 14 carbon atoms, optionally containing up to 3 oxygen atoms; ma and mb are each an integer of 2 to 5, where ma and mb are the same The powder composition according to claim 1, which can be different or different. The powder composition according to claim 1 or 2, wherein the lubricant comprises a compound selected from the group consisting of the following substances.

  The powder composition according to any one of claims 1 to 3, wherein the amide has a molecular weight of 1500 to 3000 and is present in the composition in an amount of less than 1% by weight.   The powder composition according to any one of claims 1 to 4, wherein the lubricant powder is provided at a concentration of 0.2 to 0.8% by weight of the composition.   The powder composition according to any one of claims 1 to 5, further comprising one or more additives selected from the group consisting of a binder, a process aid and a hard phase.   The powder composition according to any one of claims 1 to 6, wherein the iron-based powder is moldable, and at least 80% by weight of the lubricant powder comprises the amide oligomer.   The powder composition according to any one of claims 1 to 6, wherein the composition is essentially free of ethylene bisstearamide.   The powder composition according to any one of claims 1 to 8, wherein the iron-based powder has a carbon content of at most 0.04% by weight. In the production method of sintered products:
(a) mixing an iron-based powder with a lubricant powder as defined in any of the preceding claims;
(b) pre-heating the metal-powder composition;
(c) shaping the metal-powder composition in a preheated tool; and, optionally,
(d) sintering the molded metal-powder molding at a temperature higher than 1050 ° C. to form a sintered product;
Manufacturing method.