An investigation of the effect of Ni content and hardness on the wear behaviour of sand cast Cu-Ni-Sn alloys

2014

Wear behaviour of sand cast Cu-11Ni-6Sn alloy was studied using pin-on-disc wear tester with alloy steel disc as counterpart on dry sliding wear conditions. The alloy was prepared from pure elements and melted in an electric furnace under argon atmosphere and cast into sand moulds. The cast rods were homogenized, solution heat treated and aged. Specific wear rate and coefficient of friction were measured in a sliding speed of 191 rpm, 287 rpm and 382 rpm and different normal forces of 10 N, 15 N and 20 N. Hardness of the specimen was found to increase by the aging process and it reached its maximum value, after which it decreased. The specific wear rate was found to increase with the increase in normal load and it decreased with the increase in speed. Co-efficient of friction is independent of hardness of the alloy and dependent on both applied load and speed. The strength of the material is increased by a technique called spinodal decomposition and aging process. In the case of Cu-Ni-Sn system the various alloy composition was not tested for tribological behaviour. Only few alloy compositions are studied. So in this case we have taken Cu-11Ni-6Sn alloy composition. The products made by Cu-Ni-Sn alloy is less costlier compared to Cu-Be products without health hazard and used as high performance connector materials in electronics applications, bearing material in aerospace and mining industries, friction-reducing and anti-wear materials to make high performance bearings for aerospace, roller cone, rock bit and heavy duty mobile industrial equipment.

Section: Methodssupporting

confidence: 90%

“…The same result was obtained for other values of the load (15 N and 20 N) and speed (287 rpm and 382 rpm). It is in agreement with the previous reports [3], [7] and [8]. Hence it can be concluded that the COF is independent of the hardness of the alloy.…”

Section: Coefficient Of Friction Versus Hardnesssupporting

confidence: 93%

Dry Sliding Wear Behaviour of Sand Cast Cu-11ni-6sn Alloy

2014

“…Therefore it maybe concluded that the hardness increases with increasing aging time up to a certain limit which depends on the alloy composition and aging temperature. It was found to be consistent with previous reports [9][10][11].…”

Section: Hardnesssupporting

confidence: 94%

Effects of Aging Time on Mechanical Properties of Sand Cast AL-4.5CU Alloy

2014

An investigation was carried out to understand the effects of aging time of a cylindrical specimen on hardness, tensile strength and % elongation of sand cast Aluminium alloy (Al-4.5Cu). The alloy was melted in an electric furnace and the molten alloy was poured into sand moulds. The cast rods were tested for Vickers micro-hardness, ultimate tensile strength and % elongation. The aging time was varied from 4 to 40 hours in steps of 4 hours and the maximum hardness was achieved when the specimen was aged for 36 hours. It was found that the hardness of the alloy decreases when further aging was done. Moreover, it was observed that the tensile strength increases with increase in hardness, whereas the % elongation decreases.

“…This shows COF is independent of the hardness of the alloy. It is in consistence with previous report [9,[11][12].…”

Section: Coefficient Of Frictionsupporting

confidence: 93%

Study of Effect of Cooling Rate on Mechanical and Tribological Properties of Cast AL-6.5CU Aluminum Alloy

2014

Solidification time is known to have a large effect on the microstructure of cast Aluminium alloys and hence its properties. This study is conducted to quantify how the mechanical properties of Al-6.5 Cu alloy vary with respect to the solidification time. The solidification time is varied by varying the diameter of the cast rod; this is based on the Chvorinov's rule which gives a relation between solidification time and surface area, volume of the specimen. Mechanical properties such as Ultimate Tensile Strength, Micro-hardness are observed by experimentation and change in microstructure for all the different specimens are also studied and inferred. It is observed that as the solidification time increases, the mechanical properties tend to decrease. Further the coefficient of friction is independent of the hardness and weight loss is dependent on hardness of the alloy.