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|  MIL-V-81995(AS)
c. Preference shall be given, in selection of
carbon and low alloy steels, to compositions having the least hardenability
which will insure through-hardening of the part concerned.
d. Compositions shall be selected such that heat
treatment to the required strength and service temperatures shall preclude
temper embrittlement.
e. Steels shall be selected having ductile-brittle
fracture transition temperatures as determined by impact test below the
minimum operating temperature.
f.
Steels whose mechanical properties are developed
by cold deformation shall be so selected that the recovery temperature
will be at least 50F (10C) above the maxumum operating temperature
range.
Critical parts shall be designed and processed
g.
so as to result in no decarburization of highly stressed areas. Designs
shall preclude use of as-forged surfaces unless specific approval is
obtained from the qualifying activity.
h. The mechanical drilling of holes in martensition
steels after hardening to strength levels of 180,000 psi and above shall
be avoided whenever practicable. When such drilling is unavoidable,
detailed information concerning the processes to be used shall be submitted
to the qualifying activity for approval.
i. Any necessary straightening of parts after heat
treatment to strength levels of 180,000 psi and above shall be accomplished
at the tempering temperature, plUS (PF (-180c) minus 50~F (lOC), or the
parts shall receive a stress-relieving treatment at this temperature
immediately after straightening. Parts shall be inspected for cracks
after straightening.
j. Free-machining grades of steel shall be subject
to approval by the qualifying activity.
3.5. 1.3.2
Corrosion-resistant steels. The following limitations
shall be observed in the selection and application of corrosion resistant
steels.
a.
Unstabilized austenitic steels shall not be
fusion welded.
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