Maximum fiber stress. Maximum tensile or compressive stress in a homogeneous flexure or torsion test specimen. For a specimen loaded as a simple beam at its midpoint, maximum fiber stress occurs at mid-span and may be calculated by the formula (for rectangular specimens): S=3PL/2bd2 where S is maximum fiber stress; P, load; L, span; b, width of the beam and d, depth of the beam. For a circular cross section member loaded in torsion, maximum fiber stress may be calculated by the following formula: S=Tr/J where T is twisting moment; r, original outer radius and J, polar moment of inertia of original cross section.

最大纤维应力。均匀弯曲或扭转试样的最大拉伸应力或抗压应力。对于在中点以简单梁负荷的试样，其最大纤维应力发生在跨距中点，可通过以下公式计算（就矩形样本而言）：S = 3PL / 2bd2，其中S为最大纤维应力； P为负荷； L为跨距； b为梁的宽度，d为梁的深度。而对于受扭转负荷作用的圆形截面构件，其最大纤维应力可通过以下公式计算:S=Tr/J，其中T为扭转力矩;r为原外半径；J为原横截面的极惯性矩。

Mean stress. Algebraic difference between maximum and minimum stress in one cycle of fluctuating loading as in a fatigue test. Tensile stress is considered positive and compressive stress negative.

平均应力。于脉动负荷(如疲劳试验)循环中，最大和最小应力之间的代数差。其中，拉伸应力被认为是正的，抗压应力被认为是负的。

Mechanical hysteresis. Alternate term for elastic hysteresis.

机械滞后。弹性滞后的另一个术语。

Microhardness. Hardness of microscopic areas. Microhardness values differentiate hardness of constituents in a material.

显微硬度。是指显微区域的硬度。显微硬度值用于区分材料中各成分的硬度。

Minimum bend radius. Minimum radius to which a sheet or wire can be bent to specified angle without failure.

最小弯曲半径。是指薄板或金属丝可弯曲到指定角度而不会发生故障的最小半径。

Modulus. Alternate term for modulus of elasticity, often used in connection with rubber.

模量。弹性模量的另一种术语。通常与橡胶一起使用。

Modulus in bending. Ratio of maximum fiber stress to maximum strain with in elastic limit of stress-strain diagram obtained in flexure test. Alternate term is flexural modulus of elasticity.

弯曲模量。弯曲试验所得的应力应变图的弹性极限内纤维最大应力与最大应变之比。它又称为弯曲弹性模量。

Modulus of elasticity. Rate of change of strain as a function of stress. The slope of the straight line portion of a stress-strain diagram. Tangent modulus of elasticity is the slope of the stress-strain diagram at any point. Secant modulus of elasticity is stress divided by strain at any given value of stress or strain. It also is called stress strain ratio. Tangent and secant modulus of elasticity are equal up to the proportional limit of a material.

弹性模量。应变变化率作为应力的函数。应力-应变图中直线部分的斜率。

切线弹性模量是应力应变图上任意一点的斜率。正割弹性模量是在任何给定的应力或应变值下，其应力除以应变。它也称为应力应变比。弹性模量的正切和正割模量等于材料的比例极限。

Depending on the type of loading represented by the stress-strain diagram, modulus of elasticity may be reported as compressive modulus of elasticity (or modulus of elasticity in compression), flexural modulus of elasticity (or modulus of elasticity in flexure), shear modulus of elasticity (or modulus of elasticity in shear), tensile modulus of elasticity (or modulus of elasticity in tension) or torsional modulus of elasticity (or modulus of elasticity in torsion). Modulus of elasticity may be determined by dynamic mechanical testing where it can be derived from complex modulus.

根据应力应变图表示的负荷类型，弹性模量可记录为压缩弹性模量(或者抗压弹性模量)、弯曲弹性模量(或挠曲弹性模量)、剪切弹性模量(或切变弹性模量)、拉伸弹性模量(或张力弹性模量)或扭转弹性模量(或者在抗扭弹性模量)。此外，弹性模量可以通过动态力学试验来测定，并可以由复数模量导出。

Modulus used alone generally refers to tensile modulus of elasticity. Shear modulus is almost always equal to torsional modulus and both are called modulus of rigidity. Moduli of elasticity in tension and compression are approximately equal and are known as Young’s modulus. Modulus of rigidity is related to Young’s modulus by the equation: E = 2G (1 + r) where E is Young’s modulus (psi), G is modulus of rigidity (psi) and r is Poisson’s ratio. Modulus of elasticity also is called elastic modulus and coefficient of elasticity.

模量单独使用时，一般是指拉伸弹性模量。剪切模量几乎始终等于扭转模量，两者均称为刚性模量。而拉伸和压缩时的弹性模量近似相等，统称为杨氏模量。刚性模量与杨氏模量的关系式为:E = 2G (1 + r)，其中E为杨氏模量(psi)， G为刚性模量(psi)， r为泊松比。弹性模量又称弹性模数和弹性系数。

Modulus of rigidity. Rate of change of strain as a function of stress in a specimen subjected to shear or torsion loading. It is the modulus of elasticity determined in a torsion test. Alternate terms are modulus of elasticity in torsion and modulus of elasticity in shear.

刚性模量。是指试样在剪切或扭转负荷作用下，作为应力函数的应变变化率。它是在扭转试验中确定的弹性模量。它又称为扭转弹性模量和剪切弹性模量。

Apparent modulus of rigidity is a measure of the stiffness of plastics measured in a torsion test (ASTM D-1043). It is “apparent” because the specimen may be deflected past its proportional limit and the value calculated may not represent the true modulus of elasticity within the elastic limit of the material.

表观刚性模量是在扭转试验中测量的塑料刚度的一种度量(ASTM D-1043)。这属于“表观的”，因为试样可能会偏离其比例极限，因此计算所得值可能无法代表材料弹性极限内的真实弹性模量。

Modulus of rupture. Ultimate strength determined in a flexure or torsion test. In a flexure test, modulus of rupture in bending is the maximum fiber stress at failure. In a torsion test, modulus of rupture in torsion is the maximum shear stress in the extreme fiber of a circular member at failure. Alternate terms are flexural strength and torsional strength.

断裂模量。于弯曲或扭转试验中确定的极限强度。于弯曲试验中，弯曲的断裂模量是纤维破坏时的最大纤维应力。于扭转试验中，扭转断裂模量是圆形构件在破坏时纤维极限处的最大剪切应力。它又称为抗弯强度和抗扭强度。