AIA/NAS 531-2012 pdf download CHARTS, ROCKWELL HARDNESS
(1 ) These charts contain approximate hardness values for use in determining the condition or temper of commonly used aircraft materials. Materials and parts meeting the hardness requirements of these charts may be accepted providing other material property and processing requirements established by individual companies have been satisfactorily met. Material shall not be rejected solely on the basis of failing to meet the hardness requirements of these charts.
(2) Procurement specifications are listed for information only and may be superseded at any time.
(3) In case of conflict between these values and those given in the applicable procurement specification or individual company specification, the latter specifications, as applicable, shall govern.
(4) Additional aluminum alloy hardness values may be obtained from AMS2658. * Hardness values followed by an asterisk
(*) indicate the data were taken from procurement specifications. All other values were established on the basis of data compiled and analyzed by the subcommittee members. ** Specification numbers followed by two asterisks
(**) indicates the documents have been cancelled, superseded, inactivated, or are noncurrent.