Metallurgical testing refers to the collection of inspections and empirical examinations that are conducted on a metal to verify its properties prior to bending, shaping or other forms of physical manipulation. Metallurgical testing is used to determine the appropriateness of a particular metal for a given application.
Metallography or material testing for microstructure analysis is very important analyzing the material micro structure and also to understand the decarburization and carburization of the screw, whether the material has been properly heat treated and adheres to the parameters of the standard can be better understood by the proper analysis of metal by way of microstructure analysis and with the help of various hardness testers. Metallurgical testing may also be known as metallurgical evaluation, examination, or analysis.
Metallurgical testing typically uses microscopy to provide vital details about the structure and properties of a metal or alloy sample. The process makes use of a metallography examination or analysis.
Metallurgical testing includes an examination of the following core properties:
- Chemical Analyses
- Microstructure
- Plating/Coating Thickness
- Case Depth
- Grain size
- Surface contamination
- Carburization & decarburization
List of machines for metallurgical testing facility we have
We have in house facility of metallurgical testing with high accuracy of data & very pro level employees experience.
Metallurgical Microscope
- Model : Nikon – Dewinter
- Make : Dewinter South Korea
The microscope is equipped with ultra lens with magnification power up to 1000X. It is also equipped with features like analyser, polarizer and attached camera for measuring grain size, decarb, microstructure, inclusions, rating etc. It is attached with the computer to give image display and generate reports.
We test fasteners in carbon steel, Alloy steel, boron, Brass, Aluminium and stainless steels including duplex/super duplex, alloy 625, 718, 825, nickel aluminium bronzes alloys.
Carburizing :- The carburizing process is a diffusion heat-treatment that allows a mechanical component of steel with a low carbon content increases its tenor. After carburizing steel parts must also be subjected to quenching first and tempering after. The carburizing phases are the following:
- Preheat the furnace until it reaches the correct temperature of heating (this is variable depending both on the characteristics of the steels and on the final properties of the piece)
- The components are placed inside the furnace and left there -
a) until they reach a temperature uniformity in all their parts
b) when the process of carbon absorbing took place (carbon moves from the atmosphere of the kiln to the surface layers of the treated parts) - Subsequently, these undergo a sudden cooling in an oil, water or salt bath (so it is induced the martensitic transformation)
- Finally, it runs a tempering at low temperature.
Decarburization :- Steel heat treatment is not without risk. The consequence of non-optimal control of the heat treatment process conditions is oxidization of the carbon, which is present in the periphery of the steel fastener. As a result, a thin layer with insufficient carbon may grow on the outside of the fastener. The mechanical properties of steel are determined to a high degree by the carbon it contains. As the affected layer has a lack of carbon, this layer cannot hardened and remains relatively soft. The pitch diameter of the screw thread is therefore severely weakened,
which in turn substantially reduces the load ability of any threaded joints. Moreover, the thread friction experienced during assembly increases considerably, with the result being that the relationship between the tightening torque and the preload becomes unreliable.
This is a detrimental phenomenon for screw threads, as it unavoidably causes threads to strip when a load is applied. From the outside, it is impossible to see if decarburization has occurred. Additionally, threads do not always strip during assembly, so it could be noticed before disaster strikes.
Decarburization can only be detected with the microscopic or hardness tests described in EN ISO 898-1. In the picture from a Roll-fast made for a hardness test to check for decarburization, the completely decarburized zone is clearly visible as a white area on the screw thread’s exterior.
Simple Cutting Machine
- Model : BAINCUT - UM Auto
- Make : Chennai Metco, India
1. Cutting Capacity up to 80 mm dia. To cut and section, for preparation-with least metallurgical change.
2. Cutting Action “Y” movement table with servo system.
3. PLC with graphical touch screen display
4. Variable feed rate cutting length
5. Pre set programming & data storage up to 25 programmes
Automatic Pneumatic Mounting Press
- Model : BAINMOUNT- P Auto
- Make : Chennai Metco, India
High speed heater, direct reading pressure gauge, timer with buzzer at end of cycle. Suitable for labs with moderate number of samples. Automation offers reduced manual intervention and improved consistency. Easy mould change 1 1/4", 1 1/2"dia and 2" dia.
1. Digital temperature indicator and Digital timer with LCD Display.
2. Automatic water-cooling system.
3. Interchange size 1.1/2”, 30 mm & 40 mm mould size.
4. Wide range of sample size can be accommodated.
General Purpose Belt Grinder
- Model : Belt Grinder - BGGP
- Make : Chennai Metco, India
For flat Coarse grinding prior to fine grinding. The specimens to be ground in 60, 80 or 120 grit after cutting or moulding operation to remove surface imperfections. Useful step to remove light metallurgical damage in the specimen surface induced during cut-off operation.
1. Sturdy Tabletop model for Pre-Grinding of metallurgical specimen.
2. Aluminum Idler Pully Mechanism.
3. Easy removable Dust cover system.
4. Grain size belt as required.
Polisher / Grinder
- Model : BAINPOL-ETD
- Make : Chennai Metco, India
Rigid table top corrosion proof FRP cabinet with 8" disc polisher with flexible water jet with control valve for fine mirror polishing of sample.
1. Double disc polisher with Individual drive.
2. Variable speed 50-1000 RPM.
3. Safety emergency switch.
4. Flexible water jet with control valve.
