Brinell scale

You don't need to be Editor-In-Chief to add or edit content to WikiDoc. You can begin to add to or edit text on this WikiDoc page by clicking on the edit button at the top of this page. Next enter or edit the information that you would like to appear here. Once you are done editing, scroll down and click the Save page button at the bottom of the page.

(Redirected from Brinell hardness test)
Jump to: navigation, search

Please Take Over This Page and Apply to be Editor-In-Chief for this topic: There can be one or more than one Editor-In-Chief. You may also apply to be an Associate Editor-In-Chief of one of the subtopics below. Please mail us [1] to indicate your interest in serving either as an Editor-In-Chief of the entire topic or as an Associate Editor-In-Chief for a subtopic. Please be sure to attach your CV and or biographical sketch.

The Brinell scale characterizes the indentation hardness of materials through the scale of penetration of an indenter, loaded on a material test-piece. It is one of several definitions of hardness in materials science.

Brinelling refers to surface fatigue caused by repeated impact or overloading. It is a common cause of roller bearing failures, and loss of preload in bolted joints when a hardened washer is not used. Engineers will use the Brinell hardness of materials in their calculations to avoid this mode of failure. Fretting corrosion can cause a similar-looking kind of damage and is called false brinelling since the mechanism is different.

Proposed by Swedish engineer Johan August Brinell in 1900, it was the first widely used and standardised hardness test in engineering and metallurgy. The large size of indentation and possible damage to test-piece limits its usefulness.

The typical test uses a 10 mm diameter steel ball as an indenter with a 3,000 kgf (29 kN) force. For softer materials, a smaller force is used; for harder materials, a tungsten carbide ball is substituted for the steel ball. The indentation is measured and hardness calculated as:

\mbox{BHN}=\frac{2P}{\pi D ({D-\sqrt{(D^2-d^2)})}}

where:

P = applied force (kgf)
D = diameter of indenter (mm)
d = diameter of indentation (mm)


Common Values

When quoting a Brinell Hardness Number (BHN or, more commonly, HB), the conditions of the test used to obtain the number must be specified. The standard format for specifying tests can be seen in the example "HBW 10/3000". "HBW" means that a tungsten (chemical symbol W, from the German Wolfram) carbide ball indenter was used, as opposed to "HBS", which means a hardened steel ball. The "10" is the ball diameter in millimeters. The "3000" is the force in kilograms force.

Brinell Hardness Numbers (standard test conditions unless otherwise stated)
MaterialHardness
Softwood (e.g., pine)1.6 HBS 10/100
Hardwood2.6 to 7.0 HBS 1.6 10/100
Aluminium15 HB
Copper35 HB
Mild steel120 HB
18-8 (304) stainless steel1250 HB
Glass1550 HB
Hardened tool steel1500 - 1900 HB

Standards

  • International (ISO) and European (CEN) Standard
  • EN ISO 6506-1 : Metallic materials - Brinell hardness test - Part 1 : test method.
  • EN ISO 6506-2 : Metallic materials - Brinell hardness test - Part 2 : verification and calibration of testing machine.
  • EN ISO 6506-3 : Metallic materials - Brinell hardness test - Part 3 : calibration of reference blocks
  • ASTM E10 : : Standard method for Brinell hardness of metallic materials.

Links

Rockewell to Brinell Conversion chart: http://www.engineersedge.com/hardness_conversion.htm

See also

de:Härte#H.C3.A4rtepr.C3.BCfung_nach_Brinell et:Brinelli kõvadusfr:Échelle de Brinell he:שיטת ברינל hu:Brinell-keménység it:Scala di Brinell nl:Brinellhardheidsl:Trdota po Brinellu sv:Brinellprovning th:การวัดความแข็งบริเนล

WikiDoc Help Menu

Quick Start..

Editing basics

Advanced editing

Communicating your edits

Help Videos You Can Watch


Acknowledgement and Attribution Regarding Sources of Content

Some of the initial content on this page may be incorporated in part from copyleft sources in the public domain including wikis such as Wikipedia and AskDrWiki. Drug information for patients came from the The National Library of Medicine. Infectious disease information may have come from the Centers for Disease Control (CDC). Differential Diagnoses are drawn from clinicians as well as an amalgamation of 3 sources: 1.The Disease Database; 2. Kahan, Scott, Smith, Ellen G. In A Page: Signs and Symptoms. Malden, Massachusetts: Blackwell Publishing, 2004:3; 3. Sailer, Christian, Wasner, Susanne. Differential Diagnosis Pocket. Hermosa Beach, CA: Borm Bruckmeir Publishing LLC, 2002:7 .

Personal tools