EP 0074918 B1 19870701 - METHOD FOR SIMULTANEOUS PEENING AND SMOOTHING
Title (en)
METHOD FOR SIMULTANEOUS PEENING AND SMOOTHING
Publication
Application
Priority
- US 30071881 A 19810910
- US 30072581 A 19810910
- US 30072781 A 19810910
Abstract (en)
[origin: EP0074918A2] A method for simultaneously shot peening and smoothing includes use of relatively large, smooth, hard, spherical steel shot having a substantially uniform diameter in the range 1-2.5 mm. Titanium workpieces are provided in one step with a compressive stress layer of the order of 0.13 mm and a surface finish of better than 15 x 10<-><6> inch AA, compared to conventional peened finishes of the order of 40 x 10<-><6> inch AA. Surface finish and peening intensity are interrelated and dependent on shot diameter, mass, velocity, and energy within relatively small limits. The shot diameter is uniform within +/- 0.05 mm; the shot impact velocity is uniform within +/- 4 percent or less, in the range 1.4-12 m/s. The method is also applied to the simultaneous densification and smoothing of overlay coatings on workpieces, such as those deposited by physical vapor deposition and plasma spraying. Usually heat treatment follows the peening step. When thin edged workpieces are peened they are oscillated through critical angles with respect to the collimated shot stream used in the invention. Thus, residual compressive stresses are obtained at the edges but damage from direct impact of the large shot is avoided.
IPC 1-7
IPC 8 full level
C21D 7/06 (2006.01); C22F 1/00 (2006.01); C23C 24/04 (2006.01)
CPC (source: EP)
C21D 7/06 (2013.01); C22F 1/00 (2013.01); C23C 24/04 (2013.01)
Citation (examination)
MACHINERY AND PRODUCTION ENGINEERING, vol. 129, 4th August 1976, pages 98-102, Burgess Hill, US A. DART: "Improving fatigue strength of metals - 1"
Designated contracting state (EPC)
BE CH DE FR GB IT LI NL SE
DOCDB simple family (publication)
EP 0074918 A2 19830323; EP 0074918 A3 19840905; EP 0074918 B1 19870701; AU 556101 B2 19861023; AU 8813982 A 19830317; BR 8205191 A 19830816; DE 3276662 D1 19870806; IE 53894 B1 19890412; IE 822161 L 19830310; IL 66717 A0 19821231; IL 66717 A 19850731; IN 157173 B 19860201; SG 69287 G 19880219
DOCDB simple family (application)
EP 82630084 A 19820908; AU 8813982 A 19820908; BR 8205191 A 19820903; DE 3276662 T 19820908; IE 216182 A 19820903; IL 6671782 A 19820903; IN 1024CA1982 A 19820903; SG 69287 A 19870827