This Standard specifies the inspection procedure, inspection criteria, classi-
fication, etc. for detecting the localized overheating on ground gear surfaces by chemi-
cai etching.
The etch inspection according to this Standard is more sensitive to the surface hard-
ness change than most hardness tests. Therefore, for the detection of surface temper
after grinding, the inspection method in this Standard should be used.
Although this Standard applies to steel gears, it may also apply to steel parts such as
shafts, splines, bearings, but is not applicable to nitrided parts and stainless steels.
This etch inspection shall be performed after grinding and before additional finishing
operations.
NOTES I In this Standard, this inspection is called "nital etch" and should not
be confused with the conventional etch methods generally used to ob-
serve metallographic structure.
The International Standard corresponding to this Standard is as fol-
lows.
In addition, symbols which denote the degree of correspondence in
the contents between the relevant International Standard and JIS are
IDT (identical), MOD (modified), and NEQ (not equivalent) according
to ISOfIEC Guide 21.
ISO 14104: 1995 Gears- Surface temper etch inspection after grind-
ing (MOD)