Compacted graphite iron brake drum

• US 6,572,712 B2
• Filed: 12/14/2000
• Issued: 06/03/2003
• Est. Priority Date: 12/14/2000
• Status: Expired due to Term

• Current Assignee: Webb Wheel Products, Inc (Berkshire Hathaway Incorporated), Waupaca Foundry, Inc. (Proterial Ltd.)
• Original Assignee: Webb Wheel Products, Inc (Berkshire Hathaway Incorporated), Waupaca Foundry, Inc. (Proterial Ltd.)
• Inventors: Levering, Paul D., Powell, William L.
• Primary Examiner(s): Yee, Deborah
• Application Number:
  US09/737,172
• Publication Number:
  US 20020108823A1
• Time in Patent Office: 901 Days
• Field of Search: 188/218.XL, 188/251.K, 188/251.A, 188/251.M, 420/13, 148/321
• US Class Current: 148/321
• CPC Class Codes: C22C 33/08 Making cast-iron alloys
• CPC Class Codes: C22C 37/04 containing spheroidal graphite
• CPC Class Codes: C22C 37/10 containing aluminium or silicon
• CPC Class Codes: F16D 2200/0013 Cast iron
• CPC Class Codes: F16D 65/10 Drums for externally- or internally-engaging brakes

Abstract

A compacted graphite iron brake component for use in a braking system having a final composition of: 3.0 to about 4.0 percent carbon; 2.15 to about 2.60 percent silicon; 0.40 to about 0.90 manganese; and the balance iron. The brake component having a frictionally engageable portion with a microstructure of compacted graphite disposed in a pearlitic matrix.

Claims

1. A compacted graphite iron brake drum comprising:

(a) a base portion; and

(b) a wall defining an interior friction engagement surface adjoining said base portion, said base portion and said friction portion being composed of a material having a final composition comprising;

(i) carbon in an amount of about 3.0 to about 4.0 weight percent;

(ii) sulfur in an amount of about 0.001 to about 0.020 weight percent; and

(iii) the balance primarily iron, said base portion and said friction portion having a microstructure of compacted graphite disposed in a matrix which is greater than 50% pearlitic.

2. The compacted graphite iron brake drum of claim 1 having carbon in an amount from 3.30-3.70 weight percent.

3. The compacted graphite iron brake drum of claim 1 further comprising:

(iii) silicon in an amount of about 2.15 to about 2.60 weight percent; and

(iv) manganese in an amount of about 0.40 to about 0.90 weight percent.

4. The compacted graphite iron brake drum of claim 1 having a matrix having from greater than 0 to 50% by volume compacted graphite.

5. The compacted graphite iron brake drum of claim 3 having a matrix having from greater than 0 to 20% by volume compacted graphite.

6. The compacted graphite iron brake drum of claim 1 having from greater than 50% to 70% pearlitic matrix.

7. The compacted graphite iron brake drum of claim 5 having from 65 to 85% pearlitic matrix.

8. The compacted graphite iron brake drum of claim 1 having from greater than 50% to 65% pearlitic matrix.

9. A compacted graphite iron brake drum having compacted graphite dispersed therein, comprising:

(a) a base portion; and

(b) a wall depending upon said base portion, said wall defining an interior friction engagement surface wherein said base portion and side wall comprise;

(i) carbon in an amount of about 3.0 to about 4.0 by weight percent;

(ii) silicon in an amount of about 2.15 to about 2.60 by weight percent;

(iii) manganese in an amount of about 0.40 to about 0.90 by weight percent;

(iv) sulfur in an amount of about 0.001 to about 0.020 by weight; and

wherein said compacted graphite iron alloy has a matrix which is greater than 50% and less than 70% pearlitic with said compacted graphite disposed therein.

10. The compacted graphite iron brake drum of claim 9 comprising from greater than 50 to 60% by volume pearlitic matrix.

11. The compacted graphite iron brake drum of claim 9 comprising from 65 to 70% by volume pearlitic matrix.

12. The compacted graphite iron brake drum of claim 9 comprising from 3.30-3.70% by weight carbon.

13. The compacted graphite iron brake drum of claim 9 comprising a matrix having from greater than 0 to 50% by volume compacted graphite.

14. The compacted graphite iron brake drum of claim 9 comprising a matrix having from greater than 0 to 20% by volume compacted graphite.

15. The compacted graphite iron brake drum of claim 9 comprising from greater than 50 to 65% by volume compacted graphite.