Materials Knowledge

Stress Corrosion Cracking

Stress corrosion cracking is a failure mechanism that is caused by environment, susceptible material, and tensile stress.  Temperature is a significant environmental factor affecting cracking. For stress corrosion cracking to occur all three conditions must be met simultaneously.  The component needs to be in a particular crack promoting environment, [...]

Aluminum Alloys Grades (part 2)

5xxx Series. The major alloying element is Magnesium an when it is used as a major alloying element or with manganese, the result is a moderate-to-high-strength work-hardenable alloy. Magnesium is considerably more effective than manganese as a hardener, about 0.8% Mg being equal to 1.25% Mn, and it can be added in considerably higher quantities. Alloys [...]

Alpha and beta alloys on Titanium Alloys

Materials Alpha alloys commonly have creep resistance superior to beta alloys.  Alpha alloys are suitable for somewhat elevated temperature applications.  They are also sometimes used for cryogenic applications.  Alpha alloys have adequate strength, toughness, and weldability for various applications, but are not as readily forged as many beta alloys.  [...]

Titanium Alloys Kowledge

Materials The density of Titanium is roughly 55% that of steel.  Titanium alloys are extensively utilized for significantly loaded aerospace components.  Titanium is used in applications requiring somewhat elevated temperatures .  The good corrosion resistance experienced in many environments is based on titanium’s ability to form a stable oxide [...]

Selecting a Stainless Steel

There are a large number of stainless steels produced.  Corrosion resistance, physical properties, and mechanical properties are generally among the properties considered when selecting stainless steel for an application.  A more detailed list of selection criteria is listed below: Corrosion resistance Resistance to oxidation and sulfidation Toughness Cryogenic [...]

Stainless Steels Clasification

Stainless Steels are iron-base alloys containing Chromium.  Stainless steels usually contain less than 30% Cr and more than 50% Fe. They attain their stainless characteristics because of the formation of an invisible and adherent chromium-rich oxide surface film. This oxide establishes on the surface and heals itself in the presence of oxygen.  Some [...]

Steel Alloys Clasification

Steel Alloys can be divided into five groups Carbon Steels High Strength Low Alloy Steels Quenched and Tempered Steels Heat Treatable Low Alloy Steels Chromium-Molybdenum Steels Steels are readily available in various product forms.   The American Iron and Steel Institute defines carbon steel as follows: Steel is considered to be carbon steel when [...]

hardness structure of alloying elements

Generally, most alloying elements (excluding cobalt) delay the formation of softer microstructures and allow the higher hardness structure (martensite) to form at lower temperatures or at slower cooling rates. The alloying elements inhibit the formation of the three other quench products. Hence, they allow martensite to form at slower cooling rates. Hardness [...]