Abstract
This specification covers the powder forged ferrous materials fabricated by hot densification of atomized prealloyed or iron powders and intended for use as structural parts. The strcutural parts shall be made by hot forging of powder metallurgy preforms in confined dies with or without subsequent heat treatment. The materials shall conform to the required chemical composition for nickel, molybdenum, manganese, copper, chromium, sulfur, silicon, phosphorus, carbon, and oxygen. The mechanical properties such as yield strength, elongation, Rockwell hardness, impact energy, compressive yield strength and fatigue shal be determined using the tensile test method, Charpy V-notch impact energy test method, and hardness test method. The materials shall conform to the required surface finger oxide penetration, interparticle oxide networks, decarburization depth, and nonmetallic inclusion level.
Scope
1.1 This specification covers powder forged ferrous materials fabricated by hot densification of atomized prealloyed or iron powders and intended for use as structural parts.
1.2 This specification covers powder forged parts made from the following materials:
1.2.1 CompositionsP/F-10XX Carbon Steel (produced from atomized iron powder and graphite powder),
P/F-10CXX Copper-Carbon Steel (produced from atomized iron powder, copper and graphite powders),
P/F-11XX Carbon Steel with manganese sulfide for enhanced machinability (produced from atomized iron powder, manganese sulfide, and graphite powders),
P/F-11CXX Copper-Carbon Steel with manganese sulfide for enhanced machinability (produced from atomized iron powder, copper, manganese sulfide, and graphite powders),
P/F-42XX Nickel-Molybdenum Steel (produced from prealloyed atomized iron-nickel-molybdenum powder and graphite powder),
P/F-46XX Nickel-Molybdenum Steel (produced from prealloyed atomized iron-nickel-molybdenum powder and graphite powder),
P/F-44XX Molybdenum Steel (produced from prealloyed atomized iron-molybdenum powder and graphite powder), and
P/F-49XX Molybdenum Steel (produced from prealloyed atomized iron-molybdenum powder and graphite powder).
Note 1Alloy composition designations are modifications of the AISI-SAE nomenclature. For example: 10CXX designates a plain carbon steel containing copper and XX amount of carbon. Compositional limits of alloy and impurity elements may be different from the AISI-SAE limits. Chemical composition limits are specified in Section .
Note 2XX designates the forged carbon content, in hundredths of a percent, that is specified by the purchaser for the application. For a given specified carbon content, the permissible limits shall be as specified in .
1.2.2 Grades
Grade ADensity equivalent to a maximum of 0.5 % porosity. The minimum density of those sections of the powder forged part so designated by the applicable part drawing shall not be less than the value specified in .
Grade BDensity equivalent to a maximum of 1.5 % porosity. The minimum density of those sections of the powder forged part so designated by the applicable part drawing shall not be less than the value specified in .
1.3 Property values stated in inch-pound units are the standard. Conversion factors to SI units may be approximate.
