Microhardness measurements are consist of loads applied at ~2 N.
There are a number of different hardness tests but the most commonly used are the Rockwell and
Brinell hardness test uses a hard steel sphere (10 mm diam.) that is forced int
Cracks and flaws tend to remain closed in compression so brittle materials suchg as concrete are often
incorporated into designs so thast only compressive forces act on the paort.
The hardness test of a material measures the resistance to penetration of
The percent reduction in area describes the amount of thinning undergone by the specimen
during the test.
Yield strength, tensile strength, and modulus of elasticity decrease at higher temperatures, whereas
ductility commonly increases.
In metals, the yi
Chapter 3 Load and Stress Analysis
Plane Stress Occurs when stresses on one surface are zero.
o Here it is assumed that the cross-shears are equal such that tyx = txy, and tyz = tzy = txz = tzx = 0.
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depends on the level of porosity. The Youngs modulus of composites depends on the stiffness and
amounts of the indicidual components.
The stiffness of a component is proportional to its Youngs modulus.
Range of Elastic Moduli for Different Engineering Ma
deformation. The critical stress value needed to initiate plastic defomation is defined as the elastic limit
of the material. This is usually the stress required for dislocation motion, or slip, to be initiated.
In polymeric materials, this stress will c
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Required: (a.) Solve the problem as stated In the text (use superposition and nd the deection at B
and the maxim
MEEN 368 Fall 2015 HW Assignments
HW1 - (9/1) due 9/3
* Use full procedure in "Mohr's Circle Guidelines" instead of text instructions.
See posted solutions for Pr3-16a & Example Problem as examples of
requirements. Show stress cube and Mohr's ci
Sample Exam 1 Equations the info below, or something similar, will be placed at the bottom of the last page of
Irect = bh /12, I=d /64, J=IP=d /32; trans = VQ/Ib ; (trans)max=4V/3A ~ circular , (trans)max=3V/2A ~ rectangular
Problem 3-118# (cont'd)
For the "maximum" (i.e., "tightest") case:
Radial interference = (1.0023 1.0000)/2 = 0.00115 in
pmax = 25,875 psi
For the hub
Max. hoop stress is at inner radius (of hub; same as nominal interface radius = 0.5") = 43,125 p