EP 0049207 B1 19840912 - PROCESS FOR MACHINING THE SURFACE OF A NICKEL BASE SUPERALLOY WORKPIECE
Title (en)
PROCESS FOR MACHINING THE SURFACE OF A NICKEL BASE SUPERALLOY WORKPIECE
Publication
Application
Priority
US 19266880 A 19801001
Abstract (en)
[origin: EP0049207A1] Disclosed is a process for machining nickel-base superalloys wherein a thermal-effect process, such as laser or electric discharge machining, is first used to remove material but leaves a recast layer. Next a chemical milling process is used wherein the etchant only attacks and removes the recast layer. The etchant is comprised by volume percent of 40-60 HNO3, 5-20 HCl, and 20-55 H2O, with which is included 0.016-0.025 moles/liter FeCl3 and at least 0.008 moles/liter CuSO4. The FeCl3 improves removal rate but tends to cause unwanted pitting and intergranular attack. These tendencies are inhibited by the addition of CuSO4; preferably the molar ratio of CuSO4 to FeCl3 is 2:1. The beneficial combination of FeCl3 and CuSO4 is usable in other etchants.
IPC 1-7
IPC 8 full level
CPC (source: EP)
C23F 1/28 (2013.01)
Designated contracting state (EPC)
BE CH DE FR GB IT LI NL SE
DOCDB simple family (publication)
EP 0049207 A1 19820407; EP 0049207 B1 19840912; AU 544833 B2 19850613; AU 7562281 A 19820408; BR 8106057 A 19820608; CA 1165670 A 19840417; DE 3166048 D1 19841018; DK 395481 A 19820402; ES 505893 A0 19820616; ES 8205877 A1 19820616; IL 63859 A0 19811231; IL 63859 A 19840531; JP S5789484 A 19820603; JP S5824505 B2 19830521; NO 154759 B 19860908; NO 154759 C 19861217; NO 813191 L 19820402
DOCDB simple family (application)
EP 81630055 A 19810923; AU 7562281 A 19810923; BR 8106057 A 19810922; CA 386146 A 19810917; DE 3166048 T 19810923; DK 395481 A 19810908; ES 505893 A 19810930; IL 6385981 A 19810916; JP 15471781 A 19810928; NO 813191 A 19810921