MAGNETIC PULL-OFF GAGE, TYPE 1 - A dry film thickness gage that uses a type of spring balance to pull a small permanent magnet from the surface of the painted steel. The magnetic force holding to the surface varies inversely as a non-linear function of the distance between magnet and steel, i.e., the thickness of the dry paint film (plus any other films present). Type I refers to the gage's designation in SSPC-PA 2.
MAINTENANCE PAINTS - Coatings used to maintain manufacturing plants, offices, stores and other commercial structures, hospitals and nursing homes, schools and universities, government and public buildings, and both building and nonbuilding requirements in such areas as public utilities, railroads, roads, and highways; and including industrial paint, other than the original coating, the primary function of which is protection. Residential maintenance is excluded.
MANHOLE - A hole in the tank top to prove access to the cargo tank
MARTENSITE - A hard supersaturated solid solution of carbon in iron characterized by an acicular (needle-like) microstructure.
MASTIC - (1) A high-build coating. (2) An adhesive material.
MATERIAL SAFETY DATA SHEET (MSDS) - OSHA's established guidelines for the descriptive data that should be concisely provided on a data sheet to serve as the basis for written hazard communication programs. The thrust of the law is to have those who make, distribute, and use hazardous materials be responsible for effective communication.
MECHANICAL PROPERTIES - The properties of a material which makes it withstand external forces or effects, such as yield strength, tensile strength, ductility, impact resistance and hardness.
MESS HALL - The eating quarters
METAL DUSTING - The catastrophic deterioration of a metal exposed to a carbonaceous gas at elevated temperature.
METALLIZING - The coating of a surface with a thin metal layer by spraying, hot dipping, or vacuum deposition.
METHYL ETHYL KETONE (MEK) - A low-boiling strong solvent, similar to acetone but less volatile.
MICROMETER - (1) One millionth of a meter, abbreviated as pm. Also sometimes called a micron. Coating thickness often is expressed in micrometers; 25.4 micrometers = 1 mil. (2) A stationary or hand-held instrument used to measure thickness of free (unattached films).
MICRON - 1/1000 millimeter, or also one millionth of a meter.
MIDSHIPS - Middle of the Ship’s length
MIL - One thousandth (0.001) of an inch. 1 mil = 25.4 micrometers. The thickness of a coating on a surface is often expressed in mils or in micrometers.
MILDEW RESISTANCE - A coating's ability to resist the growth of mildew (fungus growth) on its surface. Mildew can cause discoloration and ultimate decomposition of a coating's binding medium.
MILDEWCIDE - A chemical agent, often included in exterior paints and caulks, that discourages mildew growth on the paint surface.
MILL SCALE - The heavy, bluish oxide layer formed during hot fabrication or heat treatment of steel and other metals.
MILL SCALE - The oxide layer formed during hot fabrication or heat treatment of metals.
MINERAL SPIRITS - A refined petroleum distillate having a low aromatic hydrocarbon content and low solubility; suitable for thinning of alkyd coatings.
MISCIBLE - Capable of mixing or blending uniformly.
MIST COAT - A thin tack coat, applied as a mist of spray, used to improve adhesion of a new coat to an existing partially cured coat.
MIST COAT - Also called a fog coat, a thin coat applied as a mist of spray and used as a tack coat or adhesive coat.
MIXED POTENTIAL - A potential resulting from two or more electrochemical reactions occurring simultaneously on one metal surface. - ultraviolet (UV) radiation.
MIXING RATIO - The ratio, usually by volume, of mixed components for a thermosetting coating specified by the supplier for complete curing into the desired film.
MODULUS OF ELASTICITY - A measure of the stiffness or rigidity of a material. It is actually the ratio of stress to strain in the elastic region of a material. If determined by a tension or compression test, it is also called Young’s Modulus or the coefficient of elasticity.
MOISTURE METER - Instrument used for determining water (moisture) content of materials such as wood or concrete.
MOISTURE RESISTANCE - The ability of a coating to resist swelling, blistering or other damage caused by moisture.
MOTTLED - Spots of different tones and colors next to each other resulting in a blotchy effect on the coating film.
MUD CRACKING - A paint failure that looks like cracked mud. It normally is caused by applying the paint in excessive thickness.
MURIATIC ACID - Concentrated hydrochloric acid often diluted and used for etching concrete.