4858

4562

كارشناسي ارشد

شناسايي، انتخاب مواد و ساخت مواد مهندسي

اصفهان: دانشگاه صنعتي اصفهان، دانشكده مواد

1388

ده،135ص.:مصور،جدول،نمودار

ص.ع.به فارسي و انگليسي

مهدي صالحي

28/9/88

رحمان حسيني،مرتضي شمعانيان

مهندسي مواد

ID4562

به فارسي و انگليسي: قابل رويت در نسخه ديجيتالي

Effect of Plasma Nitriding Oxiding Process Parameters on the Wear Behavior of ISI 316 Austenitic Stainless Steel A Hamidreza Abedi h abedi@ma iut ac ir June 15 2009 Department of Materials Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language Farsi Supervisor s Name Prof Mehdi Salehi isrec@cc iut ac ir Abstract In this work the microstructure and wear behavior of plasma nitrided oxidized AISI 316 austenitic stainless steel was investigated The structural mechanical and tribological properties were analyzed by using XRD SEM EDS microhardness testing and pin on disk tribotesting respectively The plasma nitriding treatment was performed at 425 450 and 475 C for 5 h with gas mixture of N2 H2 1 3 and 10 torr pressure Plasma nitriding at 450 C for 5 h produced single nitrided layers with thickness about 14 m Structural analysis indicate that the single phase produced was free from chromium nitride precipitation and possesses all the characteristics of the nitrogen S phase formed in DCPN Furthermore supersaturation of nitrogen in the S phase has expanded the F C C lattice structure of the substrate and thus shifted the corresponding XRD peaks of the substrate austenite to lower The expanded austenite N 200 planes are more widely shifted than any other planes indicating a deviation from the cubic F C C The shift of the austenite peaks to lower angles indicates compressive residual stresses in the nitrided layer Subsequently the treatment of plasma nitriding oxiding was performed with optimum parameter of plasma nitriding and oxiding temperature of 400 450 and 500 C with gas mixture of O2 H2 1 5 for 15 30 and 60 min The maximum surface hardness was obtained at plasma nitrided specimen due to the hard nitrided S phase 1350 HV 0 025 but the oxide layer formed caused the decrease of the surface hardness 500 550 HV 0 025 This can be ascribed to the lower hardness of iron oxide than iron nitrides It can be seen that a single phase magnetite Fe3O4 was produced at all oxidation treatment The nirtided layer thickness was reduced with increasing of the oxidation time in all oxidation temperatures But oxide layer thickness was increased at 400 and 450 C and reduced at 500 C with increasing of oxidation time pdfMachine A pdf writer that produces quality PDF files with ease Produce quality PDF files in seconds and preserve the integrity of your original documents Compatible across nearly all Windows platforms simply open the document you want to convert click print select the Broadgun pdfMachine printer and that s it Get yours now

مهدي صالحي

رحمان حسيني،مرتضي شمعانيان