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Ishaan PakrasiLab 1ME 330: LAB - 1Hardness and Compression TestingName: Ishaan Pakrasi ([email protected])Lab Section: AB3Professor: Dr. Iwona JasiukTA: William Davies ([email protected])
Ishaan PakrasiLab 1Abstract:In this Lab, hardness of various materials was tested using Brinell and Rockwell hardnesstests, and by performing a traditional compression test.In the first part of the Lab, we tested 4340 Steel and 2024 Aluminum using Brinell,Rockwell B and Rockwell C tests. For the Brinell test, the results for the tests wererecorded by analyzing diameter of indentation using a portable microscope andcorresponding conversion chart, and for Rockwell tests, a value was provided by thetesting machine. (Wilson® Rockwell® Model 523 microprocessor controlled hardnesstester)In the second half of the lab, we conducted a compression test on cylindrical specimensof 1045 Steel, 2024 Aluminum and PMMA, using an extensometer. The materials weretested up to a load of ~98kN, or until they showed signs of deformation through bucklingor barreling. The deformation was observed.Table of contents-1.Introduction1.1 Significance of Hardness tests1.2 Historical Background1.3 Laboratory on Hardness tests2.Experimental Procedure2.1 Materials2.2 Equipment Preparation2.3 Hardness Tests2.3.1Brinell hardness test2.3.2Rockwell hardness test2.3.3Compression test3.Results and Discussion3.13.2 O3.3 D3.4 A
Ishaan PakrasiLab 11. Introduction1.1 Significance of hardness testsHardness is a property that has direct correlation to material strength. Thus, hardness testsare a common method of inferring material strength on pre-defined scales. This method iswidely popular due to it being quick, and nondestructive. Though tensile tests are morespecific, they are more time consuming and are destructive. Thus, hardness tests arewidely used for quality control in manufacturing processes.1.2 Historical BackgroundSince ancient times, material hardness has been used to understand and categorizematerial strength. Since hardness can be obtained without damaging the shape of thecomponent, it is widely popular. In 1920, German geologist Carl Friedrich ChristianMohs in 1920 introduced he first standardized hardness test, using a scratch test todetermine material hardness.At the turn of the 18thcentury, in 1900, J.A. Brinell pioneered the first widely acceptedhardness test for materials, known as the Brinell hardness test. In the Brinell hardnesstest, a 10 mm diameter steel ball is pressed into the surface with a load from massesvarying from 500 kg to 3000 kg – depending on the material being tested. This load ismaintained for 15 seconds to ensure plastic deformation of the material being tested. Theresulting Brinell Harness Number (BHN) is defined by:BHN=2PπD(D−√D2−d2)…(1)…where,P=applied mass(kg), D=diameter of ball(mm), d=diameter ofindentation(mm)The Rockwell test was developed 1914, as a quicker and more reliable alternative to theBrinell hardness test. To accommodate a variety of materials, a number of scales ranging