- Hadfield Manganese Steel
- A specially steel which is austenitic and usually contains
approximately 12% Manganese. It is used in mining, earth-
moving equipment and in railroad track work.
- In a ferrous alloy, the property that determines the depth and
distribution of hardness induced by quenching.
- Resistance of a material to indentation as measured by such
methods as Brinell, Rockwell, and Vickers. The term hardness also
refers to stiffness of a material, or its resistance to
scratching, abrasion, or cutting.
- Head Metal
- The reservoir of metal in the feeder or riser of a mold.
- The total amount of metal produced which can be represented by one
analysis sample and one set of mechanical tests.
- Heat Treatment
- A combination of heating and cooling operations and applied to a
metal or alloy to produce desired properties and microstructures.
- High-Alloy Steel
- Ferrous alloy with more than 12 weight percent of noncarbon
- High Pressure Mold
- A strong high-density mold, made by air, hydraulic, or other
- High Stress Grinding Abrasion
- Abrasion that occurs when the abrasive is crushed between two
- Hindered Contraction
- Casting contraction during solidification and cooling which is
hindered by mold or core restraints.
- Hollow Drill Test (Trepanning)
- Removing a cylindrical sample from a metal section or structure to
determine soundness of the section.
- A process of heat treatment at high temperature intended to
eliminate or decrease chemical segregation by diffusion.
- Horizontal Axis Casting Machine
- A centrifugal casting machine in which the axis of rotation of the
mold is horizontal.
- Hot Box Process
- A furan resin-based process similar to shell coremaking; cores
produced with it are solid unless mandrelled out.
- Hot Strength (Sand)
- Tenacity (compressive, shear or transverse) of a sand mixture
determined at any temperature above room temperature.
- Hot Tear
- A crack or fracture formed prior to completion of metal
solidification as a result of hindered contraction. A hot tear is
frequently open to the surface of the casting and is commonly
associated with design limitations.
- High Strength Low Alloy Steel. Steel with relatively high
strength and impact properties. The carbon level is low and the
alloying additions are significantly less than 5 weight percent.
- Hydrogen Embrittlement
- A condition of low ductility resulting from the absorption of
hydrogen. A time dependent fracture process which results in a
loss of ductility.
- Hypereutectoid Steel
- A steel containing more than the eutectoid percentage of carbon
(0.83 wt. %).
- Hypoeutectoid Steel
- A steel containing less than the eutectoid percentage of carbon
(0.83 wt. %).
- Hysteresis (Cooling Lag)
- Difference between the critical points on heating and cooling due
to tendency of physical changes to lag behind temperature changes.