US 12,241,431 B1
Laser hardened pattern array in cylinder bores
Yi Liu, Troy, MI (US); Qigui Wang, Rochester Hills, MI (US); Richard L. Metcalf, Okemos, MI (US); Angela Zsidi Alksninis, Oxford, MI (US); Devin R. Hess, Clarkston, MI (US); Purushotham Kunduru, Macomb, MI (US); and Cherng-chi Chang, Troy, MI (US)
Assigned to GM GLOBAL TECHNOLOGY OPERATIONS LLC, Detroit, MI (US)
Filed by GM Global Technology Operations LLC, Detroit, MI (US)
Filed on Feb. 26, 2024, as Appl. No. 18/586,986.
Int. Cl. F02F 7/00 (2006.01); B23K 26/352 (2014.01); C21D 1/09 (2006.01); B23K 101/00 (2006.01); B23K 103/06 (2006.01); F02F 1/00 (2006.01)
CPC F02F 7/0085 (2013.01) [B23K 26/352 (2015.10); C21D 1/09 (2013.01); B23K 2101/006 (2018.08); B23K 2103/06 (2018.08); F02F 2001/008 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An engine block for a vehicle, comprising:
a bore surface, wherein the bore surface defines a cylinder bore and the bore surface exhibits a first microstructure; and
a pattern of a plurality of cycloidal features formed in the bore surface,
wherein the plurality of cycloidal features each exhibit a first length in a first axis and a second length in a second axis arranged 90 degrees from the first axis,
wherein the plurality of cycloidal features exhibit a ratio of the first length to the second length in a range of 1:1.5 to 1.5:1,
wherein the plurality of cycloidal features extend a depth into the bore surface in the range of 500 micrometers to 1 millimeters in depth,
wherein the plurality of cycloidal features exhibits a second microstructure including tempered martensite, and
wherein the second microstructure is different from the first microstructure.