CCT TEST , a trusted and accredited independent testing laboratory and calibration company

简体中文

Language

Save
Inquiry List( 0 )

MICROSCOPIC EXAMINATION

MICROSTRUCTURE ANALYSIS TO EVALUATE MATERIALS

At CCT in China, the team of expert metallurgical engineers offers a wide range of microstructure analysis services for metallic materials. Microscopic examination is an essential part of the analysis, which involves the study of the material's microstructural features under magnification. The properties of a material, which determine its performance under a given application, are closely linked to its structure. Our microstructure analysis services cover a broad spectrum, ranging from simple determination of parameters such as grain size or coating thickness to complete evaluation of abnormalities and failure mechanisms such as inclusions, segregation, and surface layers.


ANALYSES PERFORMED AT CCT

· Grain size (ASTM E112)

· Extent of Carburization & Decarburization

· Intergranular Attack & Oxidation

· Sensitization

·  Case/Surface Contamination

· Percent Spheroidization

· Inclusion Rating (ASTM E45)

· Plating Thickness

· Case Depth

· Carbide Precipitation

· Ferrite by Point Count (ASTM E562)

· Nodularity, Nodule Count

· Eutectic Melting

· Volume fraction of various phases or second phase particles in metals

CCT's microscopic analysis services are accredited by PRI Nadcap and A2LA ISO/IEC 17025. The examinations are conducted following comprehensive procedures and industry standards to ensure the utmost reliability of results. Once testing is completed, a thorough lab report detailing the microstructure analysis is provided to clients.


TEST METHODS/STANDARDS

· ASME Sect. IX

· ASTM A247

· ASTM A262

· ASTM E112

· ASTM E1268

· ASTM E2142

· ASTM E3

· ASTM E407

· ASTM E45

· ASTM E562

· ASTM E883

· ASTM E92

· 

Accurate preparation of samples is essential to obtain reliable results in materials testing. At CCT, we have a fully equipped metallurgical sample preparation laboratory to ensure proper preparation of all specimens required for analysis.

If you need metal microstructure analysis or microscopic examination services, feel free to contact us and provide details about your requirements. Our team will promptly provide you with a quote.


ADDED SERVICES FOR MICROSCOPIC EXAMINATION

· Digital Imaging – optical magnification from 5X to 2500X

· SEM Analysis – magnification to 30,000X

· Failure Analysis

· Weld Testing for Welder Qualification


EFFECTS OF INDUSTRIAL PROCESSES AND TREATMENTS

Metallic materials undergo various industrial processes and treatments such as casting, welding, and heat treatment to enhance their characteristics and properties for specific applications. These processes and treatments can result in residual effects like inclusions or contaminants, which can be studied and explained through microscopic analysis. Moreover, the correlation between the microstructure and material properties is often the focus of investigation.

EXTENT OF DECARBURIZATION

An instance where microscopic analysis is particularly useful is in the investigation of the effects of industrial processes and treatments on metals. Processes such as casting, welding, and heat treating are often utilized to prepare metals for specific applications or to enhance their properties. However, these processes can leave residual effects like inclusions or contaminants that may impact the material's performance. Understanding the correlation between the resulting microstructure and the material properties is essential in such cases.

 

For instance, when carbon and alloy steels are exposed to high temperatures during heat treatment, an inadequate atmosphere control in the furnace may result in a loss or gain of carbon near the surfaces of the parts. Such decarburization can render the surface soft and weak with limited wear resistance, while unwanted carburization can make the surface too brittle.

SENSITIZATION

Inadequate heat treatment of austenitic stainless steel can lead to the formation of chromium carbides on the grain boundaries due to insufficient time at the required temperature or lack of rapid quenching. This can cause the material to become brittle and vulnerable to intergranular corrosion. The issue can be detected through a sensitization test.

SEM/EDS ANALYSIS

Scanning electron microscopy is a technique that can be utilized to identify abnormalities in the material's microstructure, including inclusions, segregation, surface layers, and fracture features. By incorporating energy dispersive X-ray spectroscopy (EDS), the microstructure analysis can identify the type of inclusion and the corrodents present on the fracture face.


THE MICROSCOPIC EXAMINATION PROCESS

 

Achieving accurate and reliable microscopic examination of materials requires precise sample preparation and proper use of magnification. The process begins with carefully selecting a small sample of the material to undergo microstructure analysis, with attention given to its location and orientation. This is followed by sectioning, mounting, grinding, polishing, and etching to reveal the accurate microstructure and content of the material.

Microscopic examination is conducted using a metallurgical microscope equipped with a system of lenses, such as objectives and eyepieces, to achieve different magnifications ranging from 50X up to 1000X. For highly detailed microstructural study, Scanning Electron Microscopes (SEMs) are used, which are capable of much higher magnifications.