1.1本标准描述了一种测量通常具有表面连接孔隙的粉末冶金产品密度的方法。 1.2不渗透PM材料的密度，即浸入水中时不会增加质量的材料，可以使用试验方法确定 B311 . 1.3当前方法适用于压坯、烧结零件以及压坯和烧结试样。 1.4除用于确定密度的密度和质量值外，使用克每立方厘米（g/cm 3. )克（g）单位是长- 根据行业惯例，以英寸-磅为单位的数值应视为标准值。括号中给出的值是到国际单位制的数学转换，仅供参考，不被视为标准值。 1.5 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全和健康实践，并确定监管限制的适用性。 ====意义和用途====== 5.1使用千分尺或卡尺无法准确测量复杂形状粉末冶金零件的体积。 由于密度是单位体积的质量，因此需要一种精确的体积测量方法。阿基米德原理可用于计算浸没物体的排水量。为了使其适用于含有表面连接孔隙的粉末冶金材料，通过油浸或其他方式密封表面孔隙。 5.2压实零件或试件的生坯密度通常是为了在压装过程中提供帮助或用于质量控制目的而确定的。它还用于测定基粉、混合粉和预混料的压缩性。 5.3烧结粉末冶金零件和烧结粉末冶金试样的烧结密度用作质量控制措施。 5.4烧结轴承的浸渍密度通常是为了质量控制目的而测量的，因为通常供应和使用的轴承都是油浸的。

1.1 This standard describes a method for measuring the density of powder metallurgy products that usually have surface-connected porosity. 1.2 The density of impermeable PM materials, those materials that do not gain mass when immersed in water, may be determined using Test Method B311 . 1.3 The current method is applicable to green compacts, sintered parts, and green and sintered test specimens. 1.4 With the exception of the values for density and the mass used to determine density, for which the use of the gram per cubic centimetre (g/cm 3 ) and gram (g) units is the long-standing industry practice, the values in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. ====== Significance And Use ====== 5.1 The volume of a complex shaped PM part cannot be measured accurately using micrometers or calipers. Since density is mass per unit volume, a precise method for measuring the volume is needed. Archimedes’ principle may be used to calculate the volume of water displaced by an immersed object. For this to be applicable to PM materials that contain surface connected porosity, the surface pores are sealed by oil impregnation or some other means. 5.2 The green density of compacted parts or test pieces is normally determined to assist during press set-up, or for quality control purposes. It is also used for determining the compressibility of base powders, mixed powders, and premixes. 5.3 The sintered density of sintered PM parts and sintered PM test specimens is used as a quality control measure. 5.4 The impregnated density of sintered bearings is normally measured for quality control purposes as bearings are generally supplied and used oil-impregnated.