Brake pad and under-layer material composition
A brake pad according to an embodiment includes a friction material containing copper at 0.5 wt % or less, a back plate, and an under-layer material laminated between the friction material and the back plate and having an average loss modulus of 500 MPa or more at −50° C. to 0° C. in a bending mode.
1. A brake pad comprising:
a back plate;
an under-layer material fixed to the back plate;
a friction material fixed to the under-layer material so that the under-layer material is positioned between the back plate and the friction material;
the friction material containing copper at 0.5 wt % or less;
the under-layer material having an average loss modulus of 500 MPa or more at −50° C. to 0° C. in a bending mode.
2. The brake pad according to claim 1 , wherein:
the under-layer material is comprised of a thermosetting resin, a friction modifier, rubber, and aramid fiber;
an amount of the rubber in the under-layer material is 20 vol % or more; and
an amount of the aramid fiber in the under-layer material is 6 vol % or less.
3. The brake pad according to claim 1 , wherein the under-layer material contains iron fiber and mineral fiber, and a total amount of the iron fiber and the mineral fiber in the under-layer material is 25 vol % or more.
4. The brake pad according to claim 1 , wherein:
the under-layer material is comprised of a thermosetting resin, a friction modifier, rubber, and aramid fiber;
an amount of the rubber in the under-layer material is 20 vol % or more; and
an amount of the aramid fiber in the under-layer material is more than 0 vol % and 6 vol % or less.
5. The brake pad according to claim 1 , wherein the under-layer material is comprised of rubber in an amount 20 vol %-40 vol %.
6. The brake pad according to claim 1 , wherein the under-layer material is comprised of aramid fiber in an amount 3 vol %-6 vol %.
7. The brake pad according to claim 1 , wherein the under-layer material is comprised of iron fiber and mineral fiber in an amount 25 vol %-50 vol %.
8. The brake pad according to claim 7 , wherein the under-layer material is comprised of rubber in an amount 20 vol %-40 vol %.
9. The brake pad according to claim 7 , wherein the under-layer material is comprised of aramid fiber in an amount 3 vol %-6 vol %.
10. The brake pad according to claim 9 , wherein the under-layer material is comprised of rubber in an amount 20 vol %-40 vol %.
11. An under-layer material composition used to fabricate an under-layer material configured to be fixed to a back plate and to have friction material containing copper at 0.5 wt % or less fixed to the under-layer material to form a brake pad, the under-layer material composition comprising:
a composition of material that possesses an average loss modulus of 500 MPa or more at −50° C. to 0° C. in a bending mode.
12. A brake pad comprising:
a back plate;
an under-layer material fixed to the back plate;
a friction material fixed to the under-layer material so that the under-layer material is positioned between the back plate and the friction material;
the friction material containing copper at 0.5 wt % or less;
the under-layer material being comprised of: i) a thermosetting resin; ii) a friction modifier; iii) rubber; and iv) aramid fiber;
the under-layer material possessing an average loss modulus of 500 MPa or more at −50° C. to 0° C. in a bending mode.
13. The brake pad according to claim 12 , wherein the under-layer material is comprised of rubber in an amount 20 vol %-40 vol %.
14. The brake pad according to claim 12 , wherein the under-layer material is comprised of aramid fiber in an amount 3 vol %-6 vol %.
15. The brake pad according to claim 12 , wherein the under-layer material is comprised of iron fiber and mineral fiber in an amount 25 vol %-50 vol %.
16. The brake pad according to claim 15 , wherein the under-layer material is comprised of rubber in an amount 20 vol %-40 vol %.
17. The brake pad according to claim 15 , wherein the under-layer material is comprised of aramid fiber in an amount 3 vol %-6 vol %.
18. The brake pad according to claim 17 , wherein the under-layer material is comprised of rubber in an amount 20 vol %-40 vol %.