دراسة تأثير درجة حرارة المعاملات الحرارية على الخواص الميكانيكية و الكلال للفولاذ الكاربوني (35 CK كاربون )‎

الملخص EN

The aim of the research is to study the influence of heat treatment temperature on mechanical properties and limit fatigue of steel CK35.

Tensile, impact and fatigue rotating bending tests with the mean stress estimated to zero.

All the tests of heat treatment were conducted which include heating the steel to 840 ºC and then quenching by water and after that tempering at temperature of (200, 400, 600) ºC and then cooling in air, show that the temperatures of heat treatment improve the mechanical properties and fatigue limit before and after heat treatment.

The change in microstructure of steel before heat treatment (ferrite and pearlite) and after quenching martensite and martempering (Trostite or Sorbite) microstructures.

Shown that structural barriers that may help in depriving the growth of the crack.

The mechanical properties and fatigue limit were improved.

The electronic microscope slides-scanner (SEM) of the fractured surface showed the fatigue cracks growth which may be formed under the hard phases and then reduction in growth in the plasticity region.