M sections (Bantam Beams™, Junior Beams™)

Light footweight beams primarily used in the construction of pre-engineered housing. These beams are produced in lighter footweights, usually six to ten pounds per foot, than traditional structural products.

Machining

Refers to performing multiple processes to a piece of metal to produce a customer specified component part.

Magnesium

A light, silvery, moderately hard metallic element used in processing metals and chemicals, and in alloying aluminum to give it desired metallurgical properties.

Man-Hours per Ton (M-H/T)

This is a measure of labor efficiency — the ratio of total hours worked by steel employees to the tons shipped for a given period of time. Changes in the inventory level and work that is contracted out will affect the reported measurement.

Martensitic

Small category of stainless steel characterized by the use of heat treatment for hardening and strengthening. Martensitic stainless steels are plain chromium steels with no significant nickel content. They are utilized in equipment for the chemical and oil industries and in surgical instruments. The most popular martensitic stainless steel is type 410 (a grade appropriate for non-severe corrosion environments requiring high strength).

Matte Finish 1

A dull or grit surface appearance achieved by rolling on rolls which have been roughened by mechanical, chemical, or electrical means to various degrees of surface texture.

Mechanical Properties 1

Those properties of a material that reveal the elastic and inelastic reaction when force is applied, or that involve the relationship between stress and strain; for example, the modulus of elasticity, tensile strength, and fatigue limit. These properties have often been designated as “physical properties,” but the term “mechanical properties” is much to be preferred.

Merchant Bar

A group of commodity steel shapes that consist of rounds, squares, flats, strips, angles, and channels, which fabricators, steel service centers, and manufacturers cut, bend, and shape into products. Merchant products require more specialized processing than reinforcing bar.

Metric Ton (mt)

A unit of mass and weight equal to 1,000 kilograms, or 2,204.6 pounds.

Minimills

Normally defined as steel mills that melt scrap metal to produce commodity products. Although the minimills are subject to the same steel processing requirements after the caster as the integrated steel companies, they differ greatly in regard to their minimum efficient size, labor relations, product markets, and management style.

Molybdenum (Mo)

An alloying element used as a raw material for some classes of stainless steel. Molybdenum in the presence of chromium enhances the corrosion resistance of stainless steel.

Months of Inventory

Ratio of the end-of-period inventory to average monthly level of sales for the period.