Effect of hardness and morphology of potassium titanate on frictional wear characteristics of brake pads
by Jung Ju Lee; Sung Wook Kwon; Jong-Young Kim; Na-Ri Lee; Jae-Hwan Pee; YooJin Kim; Jung-A. Lee; Jeong-Joo Kim
International Journal of Nanotechnology (IJNT), Vol. 15, No. 6/7, 2018

Abstract: We investigated the effects of the properties of potassium titanate (PT), a raw material used in automobile brake pads, on the resulting frictional characteristics. Potassium hexatitanate, K₂Ti₆O₁₃ (PT6), with a non-fibrous shape, was synthesised by acid leaching and subsequent thermal treatment of potassium tetratitanate, K₂Ti₄O₉ (PT4), with the layered crystal structure. Comparing frictional characteristics, the brake pads including the largest sized PT6 (b, mean size ~72 μm, 980 Hv) with high mechanical hardness exhibits much higher coefficient of friction (COF) values and wear amounts of both the friction material and counter disc than the others. Our PT6 particles (a, mean size ~15 μm, hardness ~674 Hv) with the higher mechanical hardness than commercial PT6 (c, mean size ~24 μm, hardness ~310 Hv), show almost the same COF value and pad wear amount as PT6, c, despite reduced mean particle size. On the other hand, wear amounts and roughness of counter disc were found to be increased by ~30% for PT6, a, with higher mechanical hardness. This result shows mechanical hardness influences frictional wear of the disc, on the other hand, pad wear is proportional to COF, which is complicatedly affected by hardness and mean size. The area of secondary plateaus for commercial PT6 (c), with lower hardness and larger mean size than a, was larger than those of our PT6 (a); this finding indicates that the formation of the secondary plateau (contact area) is related to mean particle size of PT6 rather than hardness. As a result, our PT6 particles (a) with the higher hardness and smaller size than commercial PT6 exhibit almost the same COF values because the effects of mean size and hardness compensate each other.

Online publication date: Mon, 26-Nov-2018

The full text of this article is only available to individual subscribers or to users at subscribing institutions.

 
Existing subscribers:
Go to Inderscience Online Journals to access the Full Text of this article.

Pay per view:
If you are not a subscriber and you just want to read the full contents of this article, buy online access here.

Complimentary Subscribers, Editors or Members of the Editorial Board of the International Journal of Nanotechnology (IJNT):
Login with your Inderscience username and password:

Username:        Password:          Forgotten your password?

Want to subscribe?
A subscription gives you complete access to all articles in the current issue, as well as to all articles in the previous three years (where applicable). See our Orders page to subscribe.

If you still need assistance, please email subs@inderscience.com