نوع مقاله : مقاله پژوهشی
عنوان مقاله English
نویسندگان English
Determining the mechanical properties of materials , including fatigue properties used in structural components often presents challenges due to limitations in specimen extraction and the necessity of avoiding damage to in-service parts, especially in existing, safety - critical engineering components. To address these constraints, small - specimen testing techniques have gained considerable attention in recent years, with the Small Punch Test (SPT) being one of the most prominent methods. This study aims to evaluate the similarity between the small punch fatigue (SPF) test and the conventional uniaxial fatigue test in SS 304 stainless steel as a pseudo - non - destructive method for potential structural integrity assessment applications. For this purpose, the small punch fatigue (SPF) test response was analyzed in terms of the load–cycle relationship, hysteresis energy evolution, and specimen morphology after fatigue testing. SS 304 stainless steel specimens were prepared in accordance with the European standard C W A 15627 : 2006 and subjected to various cyclic loading levels. Post - test examinations revealed distinct beach marks on the fracture surfaces, clearly indicating fatigue crack growth under cyclic loading. The load – cycle curves obtained from the small punch fatigue test (SPF) exhibited a power - law trend 〖(F_max = 3.415 × 10 ^5 N_f ^ (-0.554) ,R 〗^ 2 = 0.96 ), comparable to the stress – cycle curves typically observed in standard uniaxial fatigue tests. Additionally, the hysteresis loop energy increased with the number of cycles, and its relationship with the number of cycles followed a power - law form 〖 (R〗 ^ 2 > 0.81). The strong correlation between the fatigue behavior measured using the small punch fatigue test (SPF) and that obtained from conventional uniaxial fatigue testing indicates that the small punch fatigue test can serve as an effective method for fatigue property evaluation of materials used in structures.
کلیدواژهها English