Mechanical Properties Of 4140 Grade Steel: Tensile Test And Analysis

An example, how one of us is explaining the content of Project Proposal and Scoping (thanks Dr Edward Palmer): “”
• Name and code of unit;
• Student’s name and ID;
• Supervisor’s name;
• Project title; Use of CSCs for wide area stabilisation of power systems
• Objective; In your words state what I have said above

• Introduction and Background; Read the introduction to my paper. State the importance of this work and some of the work which has been done.
• Description and Scope; My paper talks of groups of machines which under certain circumstances oscillate against other machine groups. Your question is what if we use CSCs
• Equipment/Tools required: Mainly Matlab

• Constraint if any; talk here about any problem that might prevent this from being implemented, for example SVCs cost a lot of money and a power company might not want to invest in an CSC just for stabilisation. They are normally used for voltage control.
• Conclusion; Talk about what you will do next which should be the literature review as well as get familiar with the problem through Matlab exercises
• References. As a start you can use my paper and some of the references in it. Make sure you use the Harvard referencing scheme. My paper uses a different scheme. You need to convert it.””

Introduction to Tensile Test and Mechanical Properties of Materials

The measure of the mechanical properties is an important aspect for engineers. The tensile test is one of test which is able to determine the behavior of the mechanical properties of the materials. The test is able to show the behavior of the different grades of the materials when under load (ASTM Committee D-20 on Plastics., ASTM Subcommittee D20.10 on Mechanical Properties., & ASTM International, 2015). More specifically, the mechanical properties of materials are dictated by the external forces which are applied to the body.

The ability to resist these forces is able to form the key mechanical properties for the materials. Simply, the mechanical properties are simply the strength of the material to resist the deformations and stresses which are imposed into the body (Jawad & Farr, 2018). Tensile test is one of the key test which can be carried out in order to determine the mechanical strength of the steel grades. The test is based on the reduction or elongation of the steel area and therefore able to measure the ductility of the metal grade.

The tensile test is able to increase the gage length of the metal. After the elongation or reduction of the gage length, the fracture of the metal specimen is measured within the gage of elongation. The elongation or reduction measure is expressed as a percentage of the original gage length of the metal specimen. In addition, the tensile test is also used to measure the tensile strength of the metal specimen (Tu, 2018). In this, the test is able to express the ration of maximum load applied to the cross-sectional area of the specimen.

The 4140 grade of steel is classified as a high tensile steel. The grade has 1% chromium molybdenum medium which is responsible for the hardened status of the steel grade and therefore making is one of the high tensile steel. The high chromium content is able to make the steel grade harder which enhances the machinability of the steel (Advances in Materials Technology for Fossil Power Plants (Conference), In Shingledecker, In Gandy, & Electric Power Research Institute, 2014).

The tensile range which is used for the manufacture of this steel grade ranges between 850 and 1000 Mpa. From the key improvement, the steel grade 4140 has increased machinability and have high feeds which makes it useful for the high speed applications.  The increased manufacturing strategy, the steel grade has increased mechanical properties which help to increase the life of the steel grade. In addition, the 4140 steel grade is an alloy, which is also known as “chrome-moly” steel.

The chromium is the major alloying element in the steel grade (Annual Conference on Experimental and Applied Mechanics, In Cloud, In Patterson, & In Backman, 2016). The major characteristics of the steel grade is that it is tough, ductile and wear resistant. The melting point of the steel grade stands at 2750⁰ F. in addition, the grade has a yield strength of between 60,000 and 105,000 psi.

The mechanical properties are important for the steel grade because they are able to determine the use of the specific materials. In order to enhance the efficiency of performing some key task, it is important to have the materials which have the correct mechanical properties (International Conference on Manufacturing Engineering and Technology for Manufacturing Growth, and In Xu, 2014). Measuring the mechanical properties is able to help in being certain that these materials will not fail so easily when loading them. Moreover, the mechanical properties help in coming with the best decision when determining the materials application (Branco, 2018). Therefore, we can say the knowledge of the mechanical properties will help in decision making of the material application purposes.

4140 Grade Steel: High Tensile Steel with Improved Machinability and Mechanical Properties

The tensile test is able to put into test the capability of the steel grade 4140 to with stand loadings and how much of the load the steel grade is able to accommodate (Sparacino, Shenton, University of Delaware & University of Delaware, 2016). Resisting the load failure is the main determination which will be achieved at the end of this project. Under load, the materials have a normal stress-strain curve which the material has to follow (Boake, 2012). This will show the amount of the load which can be applied on certain materials and be able to accommodate it. Each different characteristics of the grade will have the specific way of measuring it. For instance, the engineering stress of the grade 4140 will be obtained by the division of the load applied by the original cross-section areas of the grade.

Description and scope

In industries and work places, people are able to apply the use of the 4140 grade of steel without even the knowledge of the correct use of the steel grade. Many will just pick the steel and use it because they need to use the steel. With the test on the mechanical properties of the steel grade 4140, these people will be able to make decisions on the best use of the steel grade. Underutilization of the steel grade is a common reason why it is important to be able to carry out this test on the 4140 grade of steel. This test will be able to determine the extent at which different characteristics will be able to fail. The failure point will provide the workers with the knowledge on the perfect use of this steel grade.

Equipment and tools

To carry out the experiment, a Instron tensile test machine will be required. This is where the specimen of the 4140 grade steel will be tested to determine the mechanical properties behavior. In this machine, one end of the specimen is clumped while on the other end, the tensile force is applied on the specimen. The electromechanical version of the machine will be use. This machine uses an electric motor, gear reduction system and several screws to move the overhead up and down. The speed of the motor can be varied to achieve the required crosshead speed.

In the experiment, Matlab will be applied for the analysis of the mechanical properties. This technique will be able to have several mathematical formulas to calculate different mechanical properties from the physically determined factors after the tensile strength test of the 4140 grade steel. This will help to perfect formulate and understand more mechanical properties which are related to the few achieved factors from the tensile test machine.

Constraints

One of the major constraint which is likely to be faced during the project is the measure of the strain level. The determination of the strain level for the high tensile metals is usually high due to their resistance on straining. The strains at the end tend to be too small for some of the machines to be able to detect (In Silva, 2017). The measure of the strain for the high tensile metals is usually a test and this is applicable for the 4140 grade of steel.

Importance of Knowing Mechanical Properties for Material Application Purposes

Incorrect strain factor will lead to wrong determination of many mechanical factors which are able to depend on the value of strain to be determined. First the strain-stress curve will be wrong and this will mean a wrong conclusion on the amount of the load which the grade can be able to take. To minimize the constraint level, high precision machine will be used for this project. This will be able to ensure that variation of up to 0.0001 of the strain factors is detected. In addition, clamping of the specimen will be carried out to ensure that the material is tack at one position to avoid slipping. This is another area where the specimen slips result to wrong values.

Conclusion

In conclusion, it is important to be able to determine the mechanical properties of the 4140 grade steel. This will help in helping for the proper application of the metal grade. Due to its high tensile capability, the metal will be placed in perfect use. In addition, the workers will have the knowledge on the places where the steel grade 4140 is applicable and help in making the decision to use it instead of picking any steel.

The tensile test is the perfect method which can be applied to test the loading capability of this grade. This is because the method will help to come up with the key stress-strain curve which will help in determination of the different mechanical characteristic of the 4140 grade. With the knowledge on the mechanical properties, proper decision making on application and extend of loading of the 4140 grade steel can be made. This will help in the efficiency of working with the 4140 grade since one is aware of the level at which the grade can fail.

References

Advances in Materials Technology for Fossil Power Plants (Conference), In Shingledecker, J., In Gandy, D., & Electric Power Research Institute. (2014). Advances in Materials Technology for Fossil Power Plants: Proceedings from the Seventh International Conference, October 22-25, 2013 Waikoloa, Hawaii, USA.

Annual Conference on Experimental and Applied Mechanics, In Cloud, G. L., In Patterson, E., & In Backman, D. (2016). Joining technologies for composites and dissimilar materials: Proceedings of the 2016 Annual Conference on Experimental and Applied Mechanics. Switzerland: Springer

ASTM Committee D-20 on Plastics., ASTM Subcommittee D20.10 on Mechanical Properties., & ASTM International. (2015). Standard test method for tensile properties of plastics. West Conshohocken, PA : ASTM International, March.

Boake, T. M. (2012). Understanding Steel Design: a Handbook of Steel in Architecture. Basel: De Gruyter. 

Branco, R. (2018). High-strength steels: New trends in production and applications. New York: Nova Science Publishers, Incorporated.

In Silva, L. F. M. (2017). Materials design and applications. Cham, Switzerland: Springer.

International Conference on Manufacturing Engineering and Technology for Manufacturing Growth, and In Xu D. (2014). Engineering solutions for intensification of production: selected, peer reviewed papers from the 2014 2nd International Conference on Manufacturing Engineering and Technology for Manufacturing Growth (METMG 2014), January 20-21, 2014, Miami, State of Florida, USA.

Jawad, M. H., & Farr, J. R. (2018). Structural Analysis and Design of Process Equipment. Newark: American Institute of Chemical Engineers.

Sparacino, M. G., Shenton, H. W., University of Delaware,, & University of Delaware. (2016). The tensile performance of closed cell foam expansion joints: A study on the deleterious effects of compression set. M.C.E. University of Delaware.

Tu, H. (2018). Numerical simulation and experimental investigation of the fracture behaviour of an electron beam welded steel joint. Cham, Switzerland: Springer.