Mechanıcal
 

MECHANICAL TESTS 
Karabuk University Iron And Steel Institute Materials testing laboratory, offers a comprehensive service to perform the physical and mechanical tests especially iron and steel industry products and all other materials. The mechanical tests can help us on materials how to behave under real-life conditions. These tests provides a safe using by preventing disadvantages that may occur during the service conditions. At the same time tests are useful on the road to developing new materials.

Tensile Test

Tensile test is implemented by the ASTM E8, ASTM A370, ASTM B557 standards. Tensile test is used to determine the resistance and strenght of a material to applied force. The test sample is placed in the universal test device, the force is applied and the elongation of the material is measured using an extensometer.

The largest applied force until the moment of breaking is the Tensile Strength. The applied force when plastic deformation began is expressed The Yield Strength. Difference in length of test specimen between after and before test is defined Elongation. Considerations can be obtained from a tensile test concerning the strength, stiffness, and ductility of a material. (ASTM E8:Standard Test Methods for Tension Testing of Metallic Materials, ASTM A370:Standard Test Methods and Definitions for Mechanical Testing of Steel Products, ASTM B557:Standard Test Methods forTension Testing Wrought and Cast Aluminum- and Magnesium-Alloy Products).

Bend Test

Bend test is performed by ASTM A370, ASTM E190, ASTM E290 standards. Bend testing is a way to determine ductility of materials. Also toughness of material can be determined with bend testing. Specimen is placed in the test machine and force is applied by 3 or 4 point bend test techniques.

Bend testing can be applied to test samples in various sizes. (ASTM A370:Standard Test Methods and Definitions for Mechanical Testing of Steel Products, ASTM E190:Standard Test Method for Guided Bend Test for Ductility of Welds, ASTM E290:Standard Test Methods for Bend Testing of Material for Ductility).

Compression Test

Compression test is implemented by ASTM A370, ASTM E9 standards. Compression test is used to determine behaviour of material such as plastic flow behaviour, ductile fracture limits under compressive loads. This test is used for determining workability of metallic materials, in bulk deformation processes, etc.
A lot of materials are subjected to compression test such as; concrete, metals, plastics, ceramics, composites, etc. (ASTM A370:Standard Test Methods and Definitions for Mechanical Testing of Steel Products, ASTM E9:Standard Test Methods of Compression Testing of Metallic Materials at Room Temperature).

 

Brinell Hardness Test

Brinell hardness test is performed by ASTM E10 standard. Brinell hardness test is used for measuring the hardness of materials. The test consists of an applied load (between 500 kg and 3000 kg) for 10-30 seconds using a tungsten carbide ball on the surface of a metal sample. (ASTM E10:Standard Test Method for Brinell Hardness of Metallic Materials).

 

Vickers Hardness Test

Vickers hardness test is performed by ASTM E92, ASTM E384-11 standards. This test consists of, measured hardness of the surface of a piece of material, the base of a square pyramid-shaped tip which dipped under a certain load and measuring the diagonals of the indentation that occur after load is removed. (ASTM E92:Standard Test Method for Vickers Hardness of Metallic Materials, ASTM E384-11:Standard Test Method for Knoop and Vickers Hardness of Materials.) 

 

Knoop HardnessTest

 

Knoop hardness test is performed by ASTM E384-11 standard. Knoop Hardness Test is similar to Vickers Hardness Test. This test is applied to micro level hardness measurements. The Knoop Hardness Test is ideal for steep hardness gradients and coatings. Knoop Hardness Test is especially used for hard and brittle materials. (E384-11:Standard Test Method for Knoop and Vickers Hardness of Materials).

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Rockwell Hardness Test

Rockwell hardness test is performed by ASTM E18 standard. Rockwell hardness test is similar to Brinell hardness test. But its different sides as follows; diamond cone and hardened steel ball indenters is used in this test and Rockwell number is determined the difference in depth penetration between minor and major loads. (ASTM E18:Standard Test Methods for Rockwell Hardness of Metallic Materials).

 

Mikro Hardness Test

 

Micro hardness test is performed by ASTM E384 standard. This method is especially used for measuring the hardness of very small samples and thin sheet. Hardness of carburized, decarburized or nitrogen-hardened surfaces and coated surface is determined with this test. In addition, micro hardness test is used for measuring hardness of metallic alloy phases, glass, porcelain, metal carbides and various hard and brittle materials. (ASTM E384: Standard Test Method for Microindentation Hardness of Materials).

Impact Test

Impact test is performed by ASTM E23 standard. The impact test is the way of determining the behaviour of material exposed to a sudden load in bending, tensile or torsion. In the Impact test, drop a notch, shot an impact with a pendulum hammer on the specimen and behavior of material under the influence of the notch is determined. There are several types of impact test such as Charpy, Izod, Keyhole Impact Test.  (ASTM E23: Standard Test Methods for Notched Bar Impact Testing of Metallic Materials.)

 

Creep and Stress Relaxation Test

This test is implemented by ASTM E139-11 standard. Creep and Stress Relaxation Test is experiment that load is kept constant and measured increase in deformation over time. Creep is permanent deformation under a constant load depending on the time at high temperature. Stress relaxation is the downfall of stres depending on the time if shape displacement were held constant. Creep test is often done under tensile constraints. (ASTM E139-11: Standard Test Methods for Conducting Creep, Creep-Rupture, and Stress-RuptureTests of Metallic Material.)

 

Fatique Test

Fatique test is performed by ASTM E466 standard. This test is a method of determining the behavior of materials under fluctuating loads. A parent load and an alternative load is applied on specimen, the number of cycles, necessary for generating an error (fatique life), is saved. Typically, the test is repeated in an identical samples and the various alternating loads. Loads can be applied axially in the form of torsion or bending. (ASTM E466: Standard Test Method for Conducting Constant Amplitude Axial Fatigue Tests of Metallic Materials.)

 

Ring Flaring Test

 

Ring Flaring Test 
Ring Flaring Test is performed by ASTM A513 standard. Ring Flaring Test is expansion, 15% with an inner diameter without cracking, of a portion of a metallic pipe about 4 inches long with the help of a tool that given heat. (ASTM A513:Standard Specification for Electric-Resistance-Welded Carbon and Alloy Steel Mechanical Tubing).

Ring Flattening Test



Ring Flattening Test is performed by ASTM A513 standard. Flattening Test is a method for measuring the ductility of metallic pipes which are exposed to plastic deformation by flattening process.
This test may also be used for detection of defects in the pipes. Flattening test is a flattening process which test use a test piece cut a defined lenght from the pipe and flatten the sample in a direction perpendicular to lenght axis until the distance between straightening plates catch up a certain value. (ASTM A513:Standard Specification for Electric-Resistance-Welded Carbon and Alloy Steel Mechanical Tubing).

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Nick Break Test 



The Nick Break test is performed byAS 2205.4.2003 standard. Nick Break Test is very suitable for weld inspection in terms of speed and low cost. 
A suitable sample is supplied, the sample is prepared, be tested at the end of this process it is possible to see from the internal structure of the region. This test is performed for weldments. Cut a long and slim sample from main part, open notch upper and lower edges of the welded zone and breaking test is implemented. (AS 2205.4.2-2003: Methods for destructive testing of welds in metal-Fillet break test.)

Weldability Test

Weldability test consists of performing a chemical analysis and mechanical tests with metallography to provide information for the determination of weldability.

Rheology Test 
Rheology test is performed by ASTM D2196-10 standard. Rheology tests for the detection of material deformation under the effect of exposure to the force applied against the tension of the material is made by analysing the internal response. (ASTM D2196 - 10: Standard Test Methods for Rheological Properties of Non-Newtonian Materials by Rotational (Brookfield type) Viscometer).

Shear Test


Shear test is implemented by ASTM D1002 standard. In the Shear Test, the forces are applied parallel upper and lower surfaces of specimen different from tensile and compression test. Material will behave different from tensile and compression test under the influence of these forces and exhibit different strength and stiffness values. (ASTM D1002: Standard Test Method for Apparent Shear Strength of Single-Lap-Joint Adhesively Bonded Metal Specimens by Tension Loading (Metal-toMetal).

Torsion Testing

Torsion test is performed by ASTM A938-07 standard. Torsion testing is done to examine the behavior of materials under torsional and rotational forces. This test is especially applied on materials that exposed to torsional loads under the service conditions (shafts, bolts, cables, etc.). (ASTM A938 – 07: Standard Test Method for Torsion Testing of Wire).

Jominy Test


Jominy test is implemented by ASTM A255-10 standard. Jominy Test is a method for measuring the hardenability of steel. 
A standard test piece that have 25mm diameter and 100mm lenght is heated until austenitizing temperature and quenched to end of this sample by a water jet. After cooling, hardness measurements is starting from quenched end of this sample and hardenability curve is drawed by obtained data. (ASTM A255-10:Standard Test Methods for Determining Hardenability of Steel).

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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