Accession Number:

ADA627203

Title:

LWH & ACH Helmet Hardware Study

Descriptive Note:

Memorandum rept. 18 Nov 2010-13 Jul 2015

Corporate Author:

NAVAL RESEARCH LAB WASHINGTON DC

Personal Author(s):

• Holtz, Ronald L.
• Matic, Peter

Report Date:

2015-11-30

Pagination or Media Count:

29.0

Abstract:

NRL conducted a series of basic tests to characterize the properties of helmet screws and nuts used with the Light Weight Helmet LWH and Advanced Combat Helmet ACH. The testing included basic dimensional measurements, Rockwell hardness and Vicker s microhardness measurements, metallographic examination of the grain microstructure, basic chemical composition, tensile strength, screwnut thread pull strength, and a drop-weight impact test. Information was obtained for sets of screws and nuts taken from LWH and ACH helmets that have previously passed acceptance tests. This information is used as reference values for a series of recommended tests that can be applied to new batches of helmets or replacement screws, to detect any significant changes in the helmet hardware characteristics that could indicate a change of the ballistic performance.

Descriptors:

• *HELMETS
• *NUTS(FASTENINGS)
• *SCREWS
• ACCEPTANCE TESTS
• BALLISTICS
• CHEMICAL COMPOSITION
• HARDNESS
• IMPACT TESTS
• LIGHTWEIGHT
• MEASUREMENT
• METALLOGRAPHY
• MICROHARDNESS
• PULL TESTS
• REPLACEMENT
• SIZES(DIMENSIONS)
• STRENGTH(MECHANICS)
• TENSILE STRENGTH
• VALUE
• WARFARE

Subject Categories:

• Test Facilities, Equipment and Methods
• Protective Equipment

Distribution Statement:

APPROVED FOR PUBLIC RELEASE