Metallographic analysis

Metallographic analysis

 

Background information
It is a science that resaerch the regularity of organization form in metal material by using optical microscope,.It is also an indispensable important mean to test the organization of materials, to ensure the quality of products .With the development of science and technology, especially optical technology, the use of optical microscope performance gradually expand, such as dark field, polarization, phase contrast, as well as application of differential interference, infrared and ultraviolet light , all of these can improve the clarity and resolution of microstructure . 

 The  analyzed  project and standard

 

The Testing materials

Testing item

Testing standard


Steel and iron material

 

Routine analysis,the decarburization layer, inclusion,grain size (including general steel and stainless steel), hardness gradient, macroscopic specimens, the welding organization (including heat affected zone and weld and parent metal)

GB/T 6462-2005,GB/T 13299-1991,JB/T 7710-2007,JB/T 7713-2007,GB/T 13320-2007,GB/T 11354-2005,JB/T 9211-1999,JB/T 6141.2-1992,JB/T 6141.3-1992,QC/T 29018-2005 QC/T 262-2005,GB/T 1299-2000,JB/T 1255-2001,GB/T 7216-1987,GB/T 9441-1988,JB/T 9204-1999,GB/T 14979-1994,GB/T 9450-2005,ISO 2639:2002(E),GB/T 9451-2005,ISO 4970:1979(E),GB/T 224-1987,ISO 3887:2003(E),GB/T 5617-2005,ISO 3754:1976(E),GB/T 10561-2005,GB/T 4335-1984,

ASTM E45-2005e2,DIN 50602-1985,YS/T 347-2004,

GB/T 3246.1-2000,GB/T 9441-1988,GB/T 7216-87

GB/T 6394-2002,ASTM E112-1996(2004)e2


Copper and copper alloy 

The microstructure and grain size

QJ 2337-1992,YS/T 347-2004


aluminum and aluminum alloy

 

Casting aluminum alloy metallurgical casting Al-Si alloy metamorphism

JB/T 7946.1-1999


Casting aluminum alloy metallurgical casting Al-Si alloy burnt

JB/T 7946.2-1999


Casting aluminum alloy metallurgical casting aluminum alloy pinhole

JB/T 7946.3-1999


Casting aluminum alloy metallurgical casting aluminum bronze alloy granularity

JB/T 7946.4-1999


 The Microstructure inspection method

about distortional aluminium and aluminium alloy products

GB/T 3246.1-2000


 

 

The test process
 first of all,Metallographic analysis should prepare sample according to the regulations and all kinds of inspection standard. improper preparation may cause illusion and occur to the wrong conclusion, so it is very important to prepare the metallographic specimen.Usually metallographic sample preparation step is: sampling, Mosaic, label, grinding, polishing, etching.But not every preparation of metallographic specimen must go through the steps above.If the shape and size of selected sample is suitable and it is easy to master grind, then it don’t need to inlay.If there is inspection of non-metallic inclusions in metal materials or graphite in cast iron,then it don’t need to etch.Anyhow we should determine the sample preparation step according to the testing purpose.
 
The testing device
Metal laboratory equipped with a full range of metallographic sample preparation equipment from the  “Buehler” in the United States and the upright-put metallurgical microscope from Germany “Zeiss” ,All of these can achieve the professional metallographic analysis from the process of changing the ferrous mental into non-ferrous metals.