Experimental investigation on the various factors which influences the fatiguelife of brass materials

Rajiv Ranjan[1] , Prof. Jitendra Nath Mahto[2] , Prof. Subrato kumar soren[3]
Page No. 1-17

Brass alloy is widely used because of some attractive properties such as high electrical and thermal
conductivity. But its fatigue performance is not very well explored in literature. Thus, in the present
work, particular emphasis was given to the fatigue behavior of brass of composition 70%-CU and
30%-ZN has been investigated with the aim of studying the factors such as annealing, corrosion
and surface roughness which influence the fatigue-life of brass materials. The endurance limit of
the specimens have been determined by testing under different loads on the fatigue testing machine
and the life cycles of each specimens has been taken after failure of the specimen. Endurance limit
is defined as the alternating stress that causes failures after some specified number of cycles. This
study or investigation with the aim of studying the factors such as corrosion, annealing and surface
roughness which influence the fatigue-life of brass materials has been investigated.
Annealing was done by heating the specimens at temperature of 480 0C for 1 hours and then
allowing the specimens to cool in the control atmosphere for 3 days. Fatigue test for annealed
specimens was done and change in the fatigue endurance investigated .The specimens of groove 1
mm was prepared and the endurance limit of the specimens have been determined by testing under
different loads on the fatigue testing machine and the life cycles of each specimens has been taken
after fracture occurs on the specimen. Corrosion attack was obtained by immersion of specimens in
an salt water for 14 days in order to investigate the effect of corrosion on the fatigue-life of the
material. The corrosion agent was a solution of NaCl with a PH close to 6.5-6.8 and solution
concentration of 38%.Fatigue test at a revolution of 2800 R.P.M at room temperature and without
environment humidity control was carried out on the pre-corroded and non-corroded specimens in
order to investigate the corrosion effect on the fatigue endurance.
Finally, conclusion is listed concerning change in fatigue-life behavior due to annealing, groove
and corrosion attacks of surface of the brass materials