ENTC 207 Lab Final questions n answers rated A+ 2023

ENTC 207 Lab FinalTensile Testing Steps - correct answer 1. Place specimen in tester 2. Apply tensile load until sample breaks 3. During loading measure tensile load and length at intervals 4. Measure length after sample breaks 5. Calculations Stress - correct answer force / cross section area Y-axis psi Strain - correct answer (final length- original length) / original length X- axis in/in Modulus of elasticity - correct answer -Stress/strain (straight part of graph) -measure of stiffness of specimen Percent elongation - correct answer strain x 100 Proportional limit - correct answer -specimen is elastic but not proportional -last part of straight line Yield strength - correct answer specimen begins plastic deformation Ultimate tensile strength - correct answer highest strength achievable Breaking strength - correct answer Strength when a material breaks Ductility - correct answer Stretch Related to percent elongation Hardness testing - correct answer measure of metals resistance to indentation Hardness test types - correct answer Rockwell, Brinell, Vickers Too soft reading in hardness - correct answer Auto- negative values Manual- more than one revolution Rockwell A - correct answer minor- 10 kg major- 60 kg ball indentor Rockwell C - correct answer minor- 10 kg major- 150 kg diamond indentor Superficial loads - correct answer minor- 3 kg major- 15, 30, 45 kg N-Ball indentor (45N) T- diamond indentor Impact testing - correct answer -Charpy V notch testing -samples broken at different temperatures -machine set at max value before testing