MICROHARDNESS TESTING

VICKERS HARDNESS, KNOOP HARDNESS TEST & MORE

Microhardness testing is a reliable method to determine the hardness or deformation resistance of a material, particularly when test samples are too small or thin for macro-hardness testing. It is especially useful for evaluating the hardness of complex shapes, individual phases of a material, and surface coatings or platings. Microhardness testing can also identify the depths of case-hardened layers, decarburization or carburization, grind burns, and surface contamination.

MICROHARDNESS TESTING OFFERED AT Zhejiang Guojian Testing Technology Co., Ltd (CCT)  

At Zhejiang Guojian Testing Technology Co., Ltd (CCT) , we provide microhardness testing services that enable us to evaluate the hardness or resistance to deformation of small, thin, or complex-shaped samples, surface coatings, and individual phases of materials. The microhardness test is an effective way to identify the depth of case-hardened layers, surface contamination, and other surface features, including grind burns.

Our microhardness testing services are widely used in various industries to determine the mechanical properties of small parts, evaluate the quality of welds, and ensure conformance to hardness requirements for different surface hardening processes such as carburizing, nitriding, induction, and flame hardening.

We offer both Vickers and Knoop microhardness testing with applied loads ranging from 25 g to 1 kg. Additionally, our Vickers hardness testing capabilities include macrohardness testing, with applied loads up to 50 kg. Our microhardness testing is accredited by PRI Nadcap and ISO/IEC 17025, and all testing procedures and results are documented in certified test reports.

TEST METHODS/SPECIFICATIONS

· ASTM E92

· ASTM E384

· ASTM E1077

· ASTM B578

· ISO 6507 / ISO 9015

Conversion charts are available to compare microhardness test values to other hardness scales such as Rockwell or tensile strength.

Zhejiang Guojian Testing Technology Co., Ltd (CCT)  CAPABILITIES

· Vickers Hardness Test – micro and macro hardness with applied loads from 25 grams  to 50 kilograms

· Knoop Hardness Test – applied loads from 25 grams to 1 kilogram

· Surface Contamination

· Carburization & Decarburization

· Case Depth

· Profiles, including Welds

THE MICROHARDNESS TEST PROCESSES 

Microhardness testing involves the use of a diamond indenter (either Vickers or Knoop) to apply a controlled force of up to 1000 grams to the surface of the material being tested. This results in a small indent or permanent deformation of the material surface. The depth or diagonal length of the indent is measured microscopically, and this measurement, along with the amount of the test load, is used to calculate the material hardness using specific formulas.

For Knoop microhardness testing, a rhombus-shaped indenter is used, while for Vickers hardness testing, a square-based diamond pyramid indenter is used. Vickers hardness testing can be performed on both micro and macro scales, with a maximum test load of up to 50 kilograms. Knoop hardness numbers are often cited in conjunction with specific load values.

Accurate measurement of the indents requires the use of a special microhardness testing microscope because the indents are very small. The video below shows the microhardness testing process in action.