ENERGY NEEDS TO PRODUCE FULLY DENSE PRODUCTS VIA THE SCANPAC~® PROCESS - A LCA COMPARSION WITH CONVENTIONALLY WROUGHT PRODUCTS

摘要

Fully dense products with properties as good or better than wrought products are now produced via the Scanpac~® process. Starting material is gas atomized agglomerated powder, which is consolidated and heat treated to fully dense products, the so called MMS process. Two products have been chosen as a comparison, a stainless steel threaded fitting and a carbon steel cam lobe. The fitting is today normally produced from hot and cold rolled bar and subsequently machined while the cam lobe is normally precision forged and machined or made via conventional PM, the later if the requirements on the mechanical properties are modest. The comparison has been made by a Life Cycle Analysis (LCA) from ingoing raw material in the melting furnace to finished products measuring the total energy consumption. All aspects of energy consumption in the processes are considered, also internal transports, re-melting of circulating scarp etc. As a source of data has official institutions been used, Jernkontoret, Eurofer (European Steel organization) but also actual result figures 2009 from leading steel companies (Outokumpu and SSAB) as well as leading powder producers (Carpenter Powder Products and Erasteel Soderfors) and other suppliers of PM equipments (Avure). RESULT: The result of the comparison shows a dramatic difference in energy consumption to the advantage of the fully dense powder product. For a stainless steel fitting, the DIFFERENCE in energy consumption is approx. 13 kWhr/kg produced material from raw material, while for the cam lobe the difference is approx.5 kWhr/kg. All aspects of the economical impacts are discussed, like existing energy prices and forthcoming, gas atomized powder volumes etc, etc., but also potential markets for fully dense PM products in the future. At the same production volumes as for water atomized powder the energy needs and production costs per kg produced is the same for both powder types.