Post on 16-Dec-2015
Demo Outline (For reference)
Animated pageCharpy Experiment Simulation4
Animated pageEquations3
Animated pageTest Specimen – Support Conditions2
Animated pageImpact Test1
Page TypeTopic NameTopic Number
Impact Test
Solid Mechanics
An impact test is a dynamic test conducted on a selected specimen which is usually notched. The specimen is struck and broken by a single blow in a specially designed machine.
This demo illustrates the experiment setup, procedure and the energy absorbed in an impact test.
Impact Test
Solid Mechanics
Impact Test
Test-specimen Pendulum Machine
Aim: To measure the toughness, or energy absorption capacity of the materials.
Notch
Impact Test
Solid Mechanics
Test Specimen – Support Conditions
Charpy Test Setup
Notch
Specimen
Point of Impact
SpecimenSimple beam support
44m
Impact Test
Solid Mechanics
Notch
Izod Test Setup
Cantilever beam support
Test Specimen – Support Conditions
Impact Test
Solid Mechanics
Equations
Initial Energy (Ei) = mga = Wa
Impact Velocity = v = (2ga)
Energy after rupture (Er) = mbg = Wb
Energy absorbed by the specimen (Eab) = Ei – Er
= mga - mgb
1/2
Impact Test
Solid Mechanics
Charpy Experiment Simulation
Drag the specimen to the support and click hammer.
Specimen
Simple beam support
Hammer
1. Load the Specimen.
2. Release the Pendulum.
Impact Test
Solid Mechanics
1. Load the Specimen.
2. Release the Pendulum.
Click the Quiz button.
150
Charpy Experiment Simulation
0
Indicate P.E = 300JEnergy Absorbed = 120J
Impact Test
Solid Mechanics
Resources
Reference Links:
• http://en.wikipedia.org/wiki/Charpy_impact_test
• http://en.wikipedia.org/wiki/Izod_impact_strength_test
• http://www.matweb.com/reference/izod-impact.aspx
• http://www.steeluniversity.org/content/html/eng/default.asp?catid=151&pageid=2081271949
Impact Test
Solid Mechanics
Results of the Charpy Impact test and the Izod impact test
cannot be compared
can be compared if the specimens have the same dimensions
should be used in tandem to estimate the toughness of the material
can be compared if the pendulum / hammer has the same weight
Impact Test
Solid Mechanics
Results of an impact test
can be used directly in design equations for components
can be used in design equations for components only after empirical correlation has been obtained
can be used in design equations after adjusting for temperature difference only
cannot be used for design calculations
Impact Test
Solid Mechanics
Impact tests
are independent of specimen size
are independent of notch size
are dependent on specimen size
are dependent on notch size
Impact Test
Solid Mechanics
The temperature of the specimen
does not affect the results of the test
is directly proportional to the measured toughness
is inversely proportional to the measured toughness
affects the measured toughness differently for different materials