MIL-DTL-12560K (MR)
4.6.1.7 Heat Affected Zone. Supplier must demonstrate ability to produce plates with edge
condition that satisfies 3.2.12.2
4.6.2 Sampling for production acceptance inspection.
4.6.2.1 For chemical analysis. At least one sample for chemical analysis shall be taken from each
heat in accordance with the applicable method specified in ASTM A751 (see 6.4).
4.6.2.2 For hardness test.
4.6.2.2.1 Manual method. The Brinell hardness of each plate as heat treated in each lot up to 1.5
inches thick shall be measured in two places, one at each end of a diagonal on one plate surface.
The Brinell hardness of each plate as heat treated in each lot over 1.5 inches thick shall be
measured in four places, one at each end of a diagonal on both surfaces.
4.6.2.2.2 Image analysis method. Image analysis systems may be used to read the indentation
and compute the hardness value and if the heat treating process is continuous (not batch or
oscillation), then the amount of testing may be reduced to one surface measurement per plate up
to 1.5 inches. Plates over 1.5 inches shall be tested on both surfaces.
4.6.2.3 For Charpy V-notch impact tests. For each lot, at least one sample shall be taken for
Charpy V-notch impact tests. This sample shall be extracted from the plate near the ballistic test
sample representing the same lot. The sample shall be large enough to obtain at least three
specimens, in each direction, from each sample in accordance with 4.8.3.
4.6.2.4 Bend test. Two bend test samples shall be tested in the transverse direction.
4.6.2.5 Ultrasonic examination. All ballistic test plates greater than 0.625 inch in thickness shall
be ultrasonically examined in accordance with 4.7.3.
4.6.2.6 For ballistic acceptance samples. Unless otherwise specified in the contract or order (see
6.2), one test plate shall be submitted from each lot. The minimum plate size shall be as shown
in Table VI for the applicable thickness. The average thickness of each test plate shall be
determined at the test site by taking the average of four thickness measurements. Measurements
shall be made at least 1 inch from each edge but preferably at random in the intended impact
area. Thickness measurements for plates up to and including 2.750 inch shall be read to the
nearest 0.001 inch. Plates over 2.750 inch shall be read to the nearest 0.01 inch. If a producer
submits plates outside the specified plate tolerances (see ASTM A6/A6M or Tables III), the
procuring activity shall be notified. A Rolled Homogeneous Armor (RHA) Test Data Form (see
Figure 1) shall be completed and submitted with each ballistic test plate. In the event that plates
of the same heat rolled to a different ordered thickness but with overlapping thickness tolerance
ranges can be represented by one ballistic test plate, then only one of the ordered thicknesses
need be submitted for acceptance testing. The other ordered thickness, however, shall be
included on the applicable reporting form with the words indicating that it is represented by the
sample to be tested. However, if the two ordered thicknesses are such that each thickness
requires testing with a different type projectile as shown in Table VI, then each of the ordered
thicknesses shall be ballistically tested.
16
For Parts Inquires call Parts Hangar, Inc (727) 493-0744
© Copyright 2015 Integrated Publishing, Inc.
A Service Disabled Veteran Owned Small Business