Discussion/Conclusions Ithasbeendemonstrated thatthePMprocess maybeusedtomanufacture wearandcorrosion resistant steels[1-5,9]. Withproperheattreatment, CPM®VIMCRU®60TMiscapable ofattaining 63-65HRCafter multiple tempering intherange524-538°C (975°F-1000°F) formaximum secondary hardening and optimum stressrelieving. Thisissignificantly greater thantheattainable hardness capability of440C,and alsosomewhat betterthanthatofBG42®bearing steel.Although somecorrosion resistance issacrificed compared tolaboratory resultsobtained forlowtemperature tempering, thecorrosion resistance ofCPM® VIMCRU®60TMtempered at524-538°C (975-1000°F) isstillsignificantly betterthanthatofnon-corrosion resistant bearing steels.Highattainable hardness alsoresultsinoptimum compressive strength andwear resistance, whichweretwooftheprimary objectives ofthealloydesign. Highcompressive strength is important forstaticloadcapacity andfatiguestrength insomeadvance bearing designs. Acknowledgements Theauthors wouldliketorecognize Robert Dixon,William Stasko, andMariaSawford ofCrucible Research Centerfortheirongoing support ofthisprogram. References 1.Pearson, P.K.,Moll,J.H.,Hannigan, C.J.,Atwell, D.R."Evaluation ofP/MToolSteelsforBearing Applications," Specialty Materials andComposites Advances inPowder Metallurgy andParticulate Materials -1994,Volume 5,MetalPowder Industries Federation, Princeton, NJ,1994,pp.155-163. 2.Smith,D.W.,Leveille, A.R.,Hilton,MR.,Ward,P.C.,"Rex20/Si3N4Control Moment Gyroscope Bearing Development," 32raAerospace Mechanisms Symposium, 13-15May1998. 3.Hilton,M.R,Ward,P.C.,LeveiUe, A.R.,Park,W.,McClintock, D.A.,Smith,D.W.,"Rolling Contact Fatigue andLoadCapacity TestsofM62Bearing Steel",32°_Aerospace Mechanisms Symposium, 13-15May1998. 4.Stasko, W.,Pinnow, K.E.,Eisen,W.B.,"Development ofImproved PMWearandCorrosion Resistant ToolSteels," 4thInternational Tooling Conference, Bochum, Germany, 1996. 5.Dixon,R.B.,Stasko, W.,Pinnow, K.E.,"Particle Metallurgy ToolSteels," ASMHandbook, Volume 7, Powder MetalTechnologies andApplications, ASMInternational, Materials Park,OH,1998,pp.786802. 6.Tomasello, C.M.,Maloney, J.L.,Ward, P.C.,Materkowski, J.P.,"ANewCorrosion Resistant, Martensitic Stainless SteelForImproved Performance inMiniature Bearings," Bearing Steels:Intothe 21stCentury, ASTMSTP1327,J.J.C.HooandW.B.Green,Jr.,Ed.,American Society forTesting andMaterials, WestConshohocken, PA,1998,pp.437-446. 7.Trojahn, W.,Streit,E.,Chin,H.A.,Ehlert,D.,"Progress inBearing Performance ofAdvanced Nitrogen Alloyed Stainless Steel,Cronidur 30,"Bearing Steels:Intothe21stCentury, ASTMSTP1327,J.J.C. HooandW.B.Green,Jr.,Ed.,American Society forTesting andMaterials, WestConshohocken, PA, 1998,pp.447-459. 8.McCaffrey, T.J.,andWert,D.E.,"Development ofaStainless Corrosion Resistant Carburizing Bearing Steel,"Creative UseofBearing Steels,ASTMSTP1195,J.J.C.Hoo,Ed.,American Society forTesting andMaterials, Philadelphia, 1993,pp.137-148. 9.Stasko, W.,Pinnow, K.E.,Eisen,W.B.,"Development ofUltra-High Vanadium WearResistant Cold WorkToolSteels," Advances inPowder Metallurgy &Particulate Materials -1996,Volume 5,T.M. CadleandK.S.Narasimhan, compilers, MetalPowder Industries Federation, Princeton, NJ,1996,pp. 16-179 -17-188. Crucible, CPM®,VIMCRU®,CPM®VIMCRU®20TM,CPM®VIMCRU®60TM,andCPM®VIMCRU®80TM aretrademarks orservice marksofCrucible Materials Corporation. 440N-DURTMisatrademark ofTimken Latrobe SteelCompany. BG42®isaregistered trademark ofTimken Latrobe SteelCompany. Cronidur 308isaregistered trademark ofFAGKugelfischer Group. Pyrowear ®675isaregistered trademark ofCarpenter Technology Corporation. 143