Iron piston having selectively hardened ring groove

Patent · Tue Feb 17 04:00:00 EST 1987

OSTI ID:6740220

Brann, D E; Lindsay, J E

This patent describes a long-lasting cast iron piston body for an internal combustion engine, the piston body comprising a generally cylindrical sidewall and having an annular groove in the wall encircling the body for receiving a piston ring. The groove is defined by opposed faces that intersect the wall, the piston body being composed predominantly of gray iron characterized by an as-cast pearlitic microstructure, the groove face comprising an integrally cast, selectively hardened iron band adjacent the piston sidewall and encircling the piston body. The band is characterized by a martensitic microstructure substantially harder than the pearlitic microstructure and is effective to reduce wear resulting from a piston ring seated within the groove.

• Assignee: General Motors Corp., Detroit, MI
• Patent Number(s): US 4643079
• OSTI ID: 6740220
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
330100* -- Internal Combustion Engines
ALLOYS
CARBIDES
CARBON ADDITIONS
CARBON COMPOUNDS
CAST IRON
CRYSTAL STRUCTURE
ENGINES
HARDENING
HEAT ENGINES
INTERNAL COMBUSTION ENGINES
IRON ALLOYS
IRON BASE ALLOYS
IRON CARBIDES
IRON COMPOUNDS
MARTENSITE
MATERIALS
MECHANICAL PROPERTIES
MICROSTRUCTURE
PEARLITE
PISTONS
TRANSITION ELEMENT COMPOUNDS
WEAR RESISTANCE