Archive for the ‘Steels’ Category

Clean Steel: Part Three

Saturday, February 9th, 2008

The presence of non-metallic oxide inclusions is a major cause of incompatibility between the attainable and desirable level of cleanliness in many grades of commercial steel. Generally, inclusions degrade the mechanical properties of the steel and thereby reduce the ductility of the cast metal and increase the risk for mechanical ...

General Requirements for Rolled Steel Plates, Shapes, Sheet Piling, and Bars for Structural Use

Saturday, February 9th, 2008

This group of ASTM standard specifications covers a common requirements that, unless otherwise specified in the material specification, apply to rolled steel plates, shapes, sheet piling, and bars. This group of ASTM standard specifications covers a common requirements that, unless otherwise specified in the material specification, apply to rolled steel plates, ...

Structural Steel for Ships

Saturday, February 9th, 2008

Standard ASTM A 131M covers structural steel-shapes, plates, bars, and rivets intended primarily for use in ship construction. Material under specification A 131M is available in the following categories: * Ordinary Strength — Grades A, B, D, DS, CS, and E with a specified minimum yield point of 235Mpa, and * Higher ...

There are several forms of embrittlement in steel like intergranular embrittlement, temper embrittlement, embrittlement caused by overheating and burning.

Thursday, February 7th, 2008

Most groups of alloys can exhibit failure by cracking in circumstances where the apparent applied stress is well below that at which failure would normally be expected. Steels are no exception to this, and probably exhibit a wider variety of failure mechanisms than any other category of material. While ultimate ...

The Embrittlement and Fracture of Steels: Part Two

Thursday, February 7th, 2008

There are several forms of embrittlement in steel like intergranular embrittlement, temper embrittlement, embrittlement caused by overheating and burning. While cleavage fracture in steels is a common form of embrittlement, in many cases the embrittlement is intergranular (IG), i.e. it takes place along the grain boundaries, usually the former austenitic boundaries. ...

The Embrittlement and Fracture of Steels: Part Three

Thursday, February 7th, 2008

Significant variables, which determine ductility of steels, are to be found in the steel-making process, where the nature and distribution of inclusions is partly determined, and in subsequent solidification and working processes. Likewise, the carbide distribution will depend on composition and on steel-making practice, and particularly on the final heat ...

Brittle Fracture and Impact Testing: Part Two

Thursday, February 7th, 2008

This article describes how NDT, FTE, FTP are used in engineering design through the fracture analysis diagram (FAD). Temperature dependence of yield strength, tensile strength, and fracture strength is explained, as well as influence of various initial flaw sizes and the dynamic tear test (DT), as a highly versatile test both ...

Some effects of Alloying elements in Steel

Friday, February 1st, 2008

Alloying additions are commonly added to steels to; * increase hardenability, * improve strength, * improve mechanical properties (at operating temperature), * improve toughness for a given strength or hardness, * increase wear resitance, * improve magnetic properties. Increasing the hardenability means that pearlite transformation will be delayed to longer times. This means it is easier to ...

Elements of Steel

Friday, February 1st, 2008

It's not easy to imagine modern life without stainless steel. This interactive activity and illustrated text from the AMERICAN EXPERIENCE Web site offers an in-depth explanation of steel and other alloys and how they've affected modern technology. An interactive table displays the contents and characteristics of seven elements that are ...

Thermal Response to Fire of Insulated Cylindrical Steel Elements

Friday, February 1st, 2008

Department of Fire Protection Engineering University of Maryland, College Park, MD 20742, USA Standard calculation methods are used in current design practice in the United States to determine the fire resistance rating of structural steel elements protected with spray-applied fire resistive materials (SFRMs). These calculation methods are based on simplified analysis ...