US 11,992,880 B1
Acoustical dampening powder metal parts
Peter G. Imbrogno, Dubois, PA (US)
Assigned to Keystone Powdered Metal Company, St, Marys, PA (US)
Filed by Peter G. Imbrogno, Dubois, PA (US)
Filed on Jul. 21, 2020, as Appl. No. 16/934,580.
Claims priority of provisional application 62/877,043, filed on Jul. 22, 2019.
Int. Cl. B22F 7/00 (2006.01); B22F 5/08 (2006.01)
CPC B22F 7/008 (2013.01) [B22F 5/08 (2013.01); B22F 2302/40 (2013.01); B22F 2304/10 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A powder metal part which consists of a sintered powder metal composition, wherein the powder metal composition consists of a coarse graphite wherein the coarse graphite is present at a level which is within the range of 1 weight percent to 5 weight percent, optionally nickel, optionally molybdenum, optionally copper, optionally phosphorus, optionally magnesium, optionally silicon, optionally chromium, optionally aluminum, optionally titanium, optionally vanadium, optionally calcium, optionally zinc, and optionally cobalt, and optionally 0.02 to 2% of a standard graphite having a D50 particle size distribution which is within the range of 8 μm to 14 μm and a D90 particle size distribution which is within the range of 15 μm to 21 μm, with the balance of the powder metal composition being iron, wherein the coarse graphite is of a particle size wherein at least 30 percent of the coarse graphite will not pass through a 325 mesh screen, and wherein the powder metal part is a gear.