The present invention concerns an iron-based powder metallurgical composition comprising an iron or iron- based powder and a particulate composite lubricant, said composite lubricant comprising particles having a core comprising a solid organic lubricant having fine carbon particles adhered thereon. The invention further relates to the particulate composite lubricant and a method for producing the same.

Lubricant for powder metallurgical compositions

A comparison is made of various types of lubricant on the basis of their molecular structures and how these affect the properties of the test specimens obtained. The substances considered possess long hydrocarbon chains, with amide or hydroxyl functional groups at one end of the molecule. The variation in density and hardness of compacted and sintered iron parts with type of lubricant used is reported. The present lubricants, being fully organic, provide certain advantages with respect to traditional lubricants, since their combustion is complete, leaving no residues in the metal part and producing no toxic fumes. The tested lubricants provided green and sintered density results and sintered hardness values that are higher than those obtained with zinc stearate. PM/0429

J. Puyuelo

Papers

Possible alternative lubricants for processing iron powders