Click for new scientific resources and news about Corona[COVID-19]

Paper Information

Journal:   MODARES MECHANICAL ENGINEERING   MARCH 2018 , Volume 18 , Number 1 ; Page(s) 103 To 110.
 
Paper: 

EVALUATION OF SURFACE ROUGHNESS EFFECT ON FATIGUE LIFE IN DRILLING OF HARDENED STEEL

 
 
Author(s):  RASTI AMIR, SADEGHI MOHAMMAD HOSSEIN*, SABBAGHI FRASHI SINA
 
* DEPARTMENT OF MECHANICAL ENGINEERING, TARBIAT MODARES UNIVERSITY, TEHRAN, IRAN
 
Abstract: 

In this study, the effect of surface roughness on fatigue life was investigated in drilling process of AISI4340 steel. Three hole making methods including drilling with and without pre-drill and helical milling were utilized. In order to study the effect of surface roughness and process parameters on fatigue strength, the two main cutting parameters including cutting speed (Vc) and feed rate (fz) were changed at 5 levels using the response surface method. Five main parameter of surface roughness profile including Rz, Rt, Ra, Rq, and Rsm were measured in each experiment. Then, the fatigue life of specimens were obtained using fatigue tests. Regarding the validation experiments, 13 fatigue tests were carried out for each drilling strategy (39 fatigue tests totally). Investigation of surface texture showed the signs of the tool path, scratches by the chip collisions and ploughing on whole surfaces in the conventional drilling. These effects were negligible in other processes. Accordingly, the highest roughness was observed in conventional drilling, drilling with pre-drill and helical milling processes respectively. Also, the fatigue life estimation model based on Rz had the best estimation with an average error of 4.4%. In fact, the fatigue life is more dependent on the difference between adjacent peaks and valleys. It was also observed that a model based on the roughness parameter will decrease the maximum prediction error of the fatigue life from 16.4% to 7.5% compared to a model based on the cutting parameters.

 
Keyword(s): DRILLING, FATIGUE LIFE, SURFACE ROUGHNESS, SURFACE TEXTURE
 
References: 
  • ندارد
 
  Persian Abstract Yearly Visit 54
 
Latest on Blog
Enter SID Blog