Low alloyed steel powder

Abstract

A water atomised prealloyed iron-based steel powder is provided which comprises by weight-%: 0.4-2.0 Cr, 0.1-0.8 Mn, less than 0.1 V, less than 0.1 Mo, less than 0.1 Ni, less than 0.2 Cu, less than 0.1 C, less than 0.25 O, less than 0.5 of unavoidable impurities, and the balance being iron.

1 . A water atomised prealloyed iron-based steel powder which comprises by weight-%:
 0.4-2.0 Cr,   0.1-0.8 Mn,   less than 0.1 V,   less than 0.1 Mo,   less than 0.1 Ni,   less than 0.2 Cu,   less than 0.1 C,   less than 0.25 O,   less than 0.5 of unavoidable impurities, and   the balance being iron.   
     
     
         2 . The iron-based steel powder according to  claim 1 , wherein the content of Cr is at most 1.8 weight %. 
     
     
         3 . The iron-based steel powder according to  claim 1 , wherein the content of Cr is at least 0.5 weight-%. 
     
     
         4 . The iron-based steel powder according to  claim 1 , wherein the content of Mn is at least 0.2 weight %. 
     
     
         5 . The iron-based steel powder according to  claim 1 , wherein the content of Mn is at most 0.7 weight %. 
     
     
         6 . The iron-based steel powder according to  claim 1 , wherein the sum of the chromium and manganese content is less than 2.5 wt %. 
     
     
         7 . The iron-based steel powder according to  claim 1 , wherein the content of Cr is 0.4-0.6 weight-%, and the content of Mn is 0.6-0.8 weight-%. 
     
     
         8 . The iron-based steel powder according to  claim 1 , wherein the content of Cr is at least 0.7 weight-%, and the content of Mn is at most 0.5 weight-%. 
     
     
         9 . The iron-based steel powder according to  claim 1 , wherein the content of Cr is at least 1.0 weight-%, and the content of Mn is at most 0.4 weight %. 
     
     
         10 . An iron-based powder composition comprising a steel powder according to  claim 1  mixed with 0.35-1% by weight of the composition of graphite, 0.05-2% by weight of the composition of lubricants, optionally copper in an amount up to 3% by weight, and optionally hard phase materials and machinability enhancing agents. 
     
     
         11 . A method of producing a sintered component comprising the steps of:
 a) preparing an iron-based steel powder mixture according to  claim 10 ,   b) subjecting the composition to compaction between 400 and 2000 MPa,   c) sintering the obtained green component in a reducing atmosphere at temperature between 1 000-1 400° C., and   d) optionally forging the heated component at a temperature above 500° C. or subjecting the obtained sintered component to a heat treatment or hardening step.   
     
     
         12 . A sintered component produced from the powder composition according to  claim 10  having a pearlitic/ferritic micro structure. 
     
     
         13 . The iron-based steel powder according to  claim 2 , wherein the content of Cr is at least 0.5 weight-%. 
     
     
         14 . The iron-based steel powder according to  claim 1 , wherein the content of Mn is at least 0.3 weight-%. 
     
     
         15 . The iron-based steel powder according to  claim 1 , wherein the content of Mn is at most 0.6 weight-%. 
     
     
         16 . The iron-based steel powder according to  claim 1 , wherein the sum of the chromium and manganese content is less than 2.3% by weight. 
     
     
         17 . The iron-based steel powder according to  claim 1 , wherein the sum of chromium and manganese content is less than 1.9% by weight. 
     
     
         18 . The iron-based steel powder according to  claim 1 , wherein the content of Mn is 0.7 to 0.8% by weight. 
     
     
         19 . The iron-based steel powder according to  claim 1 , wherein the content of Cr is at least 1.0 weight-%, and the content of Mn is at most 0.3 weight-%. 
     
     
         20 . An iron-based powder composition comprising a steel powder according to  claim 2  mixed with 0.35-1% by weight of the composition of graphite, 0.05-2% by weight of the composition of lubricants, optionally copper in an amount up to 3% by weight, and optionally hard phase materials and machinability enhancing agents.