عنوان :
ارزيابي تاثير عمليات حرارتي بر رفتار خستگي فولاد زنگ نزن
مقطع تحصيلي :
كارشناسي ارشد
گرايش تحصيلي :
شناسايي و انتخاب مواد
محل تحصيل :
اصفهان: دانشگاه صنعتي اصفهان، دانشكده مهندسي مواد
صفحه شمار :
چهارده، 85ص.: مصور
استاد راهنما :
فخرالدين اشرفي زاده
توصيفگر ها :
پيرسختي , شبكه عصبي مصنوعي , الگوريتم ژنتيك , نمودار S-N
استاد داور :
علي شفيعي، ابوذر طاهري زاده
تاريخ ورود اطلاعات :
1395/07/12
چكيده انگليسي :
86 Isfahan University of Technology Department of Materials Engineering Evaluation of heat treatment effect on fatigue behavior of 17 4 PH stainless steel Sayyed Ali Razavi a razavi@ma iut ac ir June 19 2016 Department of materials engineering Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiSupervisor Fakhredin Ashrafizade Prof Email ashrafif@cc iut ac irAbstract17 4 PH alloy is a precipitation hardening stainless steel with a desirable combination ofhigh corrosion resistance and good mechanical properties achieved through appropriateage hardening treatment The aim of this research was to obtain fatigue curves for twocommon age hardening cycles known as H900 and H1150 and to study the conditions foroptimum heat treatment of this alloy For this purpose 17 4PH stainless steel in the formof 9 8 mm diameter rods was used as the experimental material To ensure the uniformityof heat treatment condition the as received alloy was solution annealed at 1050 C for 30min followed by oil quenching at room temperature To study the age hardening behaviorof the alloy the solution annealed specimens were aged in the range 400 to 600 C up to240 min and age hardening curves were obtained To study the variation of hardness in theageing process Artificial Neural Network ANN was applied Ageing at 464 C for 129min was determined by a combination of ANN and Genetic Algorithm GA to achievemaximum hardness value this heat treatment cycle was called A460 2 Ageing processeswere applied to 17 4PH stainless steel specimens based on A460 2 A480 1 H900 A620 4 H1150 and SA solution annealed conditions Microstructural examinations andhardness measurements were carried out and in addition other mechanical propertiesincluding tension and fatigue tests were performed Results of tensile tests showed thatA460 2 condition with 44 Rockwell C hardness and Ultimate tensile strength of 1467 MPaproduced the optimum hardness and strength in 17 4PH stainless steel Data obtained fromS N curves revealed endurance limits between 525 to 700 MPa in the investigatedspecimens It was concluded that the fatigue limit of 17 4PH stainless steel increased as thetoughness thus optimum ageing cycle must be determined accordingly Key words 17 4PH stainless steel age hardening Artificial Neural Network GeneticAlgorithm fatigue S N curve
استاد راهنما :
فخرالدين اشرفي زاده
استاد داور :
علي شفيعي، ابوذر طاهري زاده
