| LAP WELD |
TWO PIECES OF METAL
LAPPED, THEN WELDED. NORMALLY THE EDGES ARE BEVELED OR SCARFED
FOR BETTER WELDING. |
| LEVELING |
FLATTENING ROLLED METAL BY PASSING IT
THROUGH ROLLERS OR BY STRETCHING THE SHEET. (STRETCHER LEVELING) |
| LIGHT
METALS |
LOW-DENSITY METALS
SUCH AS ALUMINUM, MAGNESIUM, TITANIUM, BERYLLIUM OR OTHER ALLOYS. |
| LOW
CARBON STEELS |
STEEL WHICH
CONTAINS 0.10 - 0.30 % CARBON, AND LESS THAN 0.60% MANGANESE. |
| M B GRADE |
A STEEL WIRE
(.45/.75 C) WIDELY USED FOR SPRINGS. |
| MACHINABILITY
|
THE RELATIVE EASE
OF MACHINING A METAL. |
| MACHINABILITY
INDEX |
STANDARDIZED TEST
OF RELATIVE MACHINABILITY. |
| MACRO-ETCH TEST |
EVALUATES THE SOUNDNESS AND
HOMOGENEITY OF MATERIAL BY IMMERSING A SAMPLE OF THE STEEL IN HOT ACID AND
EXAMINING THE ETCHING.
|
| MACROSCOPIC
|
VISUAL INSPECTION
WITH EITHER THE NAKED EYE OR UNDER LOW MAGNIFICATION.
|
| MAGNETIC-PARTICLE INSPECTION |
A NONDESTRUCTIVE METHOD OF INSPECTION
TO DETERMINE THE EXISTENCE AND EXTENT OF POSSIBLE DEFECTS IN FERROMAGNETIC
MATERIALS.
|
| MALLEABILITY
|
THE PROPERTY THAT
DETERMINES THE EASE OF DE- FORMING A METAL WHEN THE METAL IS SUBJECTED TO
ROLLING OR HAMMERING. THE MORE MALLEABLE, THE EASIER TO WORK.
|
| MARTENSITE
|
A DISTINCTIVE
NEEDLE-LIKE STRUCTURE EXISTING IN STEEL AS A TRANSITION STAGE IN THE
TRANSFORMATION OF AUSTENITE. IT IS THE HARDEST CONSTITUENT OF STEEL OF
EUTECTOID COMPOSITE- ITION. IT IS THE CHIEF COMPOSITION OF HARDENED TOOL
STEEL. |
| MATTE OR MATTE FINISH |
NOT AS SMOOTH AS NORMAL MILL FINISH.
PRODUCED BY ETCHING OR BY ROLLING WITH ROUGHENED ROLLS. |
| MECHANICAL
PROPERTIES |
THE PROPERTIES OF A
MATERIAL THAT REVEAL ITS ELASTIC AND INELASTIC BEHAVIOR WHEN FORCE IS
APPLIED, THEREBY INDICATING ITS SUITABILITY FOR MECHANICAL APPLICATIONS: FOR
EXAMPLE , MODULUS OF ELASTICITY, TENSILE STRENGTH, ELONGATION, HARDNESS AND
FATIGUE LIMIT. |
|
MICROSTRUCTURE |
THE STRUCTURE OF POLISHED AND ETCHED METALS AS REVEALED BY
A MICROSCOPIC MAGNIFICATION OF 10 DIAMETERS OR MORE.
|
| MODULUS OF ELASTICITY |
A MEASURE OF THE
RIGIDITY OF METAL. ALSO CALLED THE "COEFFICIENT OF ELASTICITY". |
| METALLOID
|
IN STEEL IT COVERS
ELEMENTS COMMONLY PRESENT IN SIMPLE STEEL.. CARBON, MANGANESE, PHOSPHORUS,
SILICON AND SULFUR. |
| MILL EDGE |
EDGE OF SHEET,
PLATE OR STRIP WHICH IS UNTRIMMED |
| MILL FINISH |
AS PRODUCED BY
MILL. NORMALLY DULL. |
| MUNTZ
METAL |
A REFRACTORY METAL.
60 % COPPER AND 40% ZINC. USED FOR CASTINGS AND HOT-WORKED PRODUCTS. HIGH
STRENGTH BRASSES ARE DEVELOPED FROM THIS BY ADDING OTHER ELEMENTS. |
| MUSIC
WIRE |
THIS IS THE HIGHEST
TENSILE (POLISHED) WIRE MADE. |
| NICKEL SILVER |
COPPER BASED ALLOY
WITH 20-45% ZINC AND 5-30% NICKEL.
|
| NIOBIUM (Nb) |
SEE COLUMBIUM NITRIDING - INTRODUCING NITROGEN TO HARDEN FERROUS STEEL.
|
| NITRIDING STEEL |
STEEL WHICH IS
PARTICULARLY SUITED FOR THE NIT- RIDING PROCESS. IT FORMS A VERY HARD AND
ADHERENT SURFACE UPON PROPER NITRIDING. (.20-.40 C, .90-1.50 Ch,
.15-1.0 Mo, .85-1.20 AL) |
| NON-FERROUS METALS |
METALS WITH NO OR
LITTLE IRON.
|
| NORMALIZING
|
HEATING A FERROUS
ALLOY TO A SUITABLE TEMP- ATURE ABOVE THE TRANSFORMATION RANGE AND
THEN COOLING IN AIR TO A TEMPERATURE SUBSTANTIALLY BELOW TRANSFORMATION
RANGE. IT REFINES THE CRYSTAL STRUCTURE AND RELIEVES STRESS
|
| OIL HARDENING STEEL |
STEEL WHICH
IS HARDENED BY HEAT TREATMENT AND QUENCHED IN OIL.
|
| OLSON TEST |
A METHOD OF
MEASURING THE DUCTILITY AND DRAWING PROPERTIES OF STRIP OR SHEET METAL. THE
METAL IS DRAWN OVER A BALL UNTIL THERE IS A FRACTURE.
|
| OPEN HEARTH FURNACE |
A TYPE FURNACE
WHERE THE FLAME PASSES OVER THE CHARGE IN THE HEARTH, CAUSING THE CHARGE TO
BE HEATED BOTH BY DIRECT FLAME AND RADIATION FROM THE LOW ROOF AND SIDEWALLS
OF THE FURNACE. |
| ORANGE
PEEL |
THE PEBBLE-GRAINED
SURFACE WHICH DEVELOPS IN FORMING OF METALS WITH COURSE GRAINS.
|
|
OSCILLATED WOUND |
COIL
WOUND ON A REEL LIKE THREAD, AS OPPOSED TO RIBBON OR PANCAKE WOUND WHICH
IS WOUND SIMILAR TO A ROLL OF TAPE.
|
| ORIENTATION
|
HAS TO DO WITH THE
ARRANGEMENT OF CRYSTAL DIRECTION IN A PLANE. EITHER "PREFERRED " OR
"RANDOM". |
|
OXIDATION |
THE ADDING OF OXYGEN TO A COMPOUND. EXPOSURE TO ATMOSPHERE SOMETIMES
RESULTS IN OXIDATION OF THE EXPOSED SURFACE RESULTING IN A STAINING OR
DISCOLORATION. INCREASED TEMPERATURE INCREASES THE OXIDATION.
|
| OXIDE
|
A COMPOUND OF
OXYGEN WITH ANOTHER ELEMENT. |
| PACK ROLLING
|
ROLLING TWO OR MORE
PIECES OF STEEL TOGETHER. PACK ROLLING IS OFTEN USED FOR ROLLING SHEET INTO
THIN FOIL. |
| PASSIVATING
|
THE CLEANING
OF METAL OR PART BY IMMERSION IN A ACID BATH. USUALLY DONE AFTER
FABRICATION.
|