Fracture Definition and 60 Threads

So I am trying to find the amount of energy needed to break apart stone into different sized chunks (when either punching it or blowing it up) and I'm using this method to estimate it: Assume the object got broken up into cubes of the desired diameter Find the surface area of all the cubes...

From Stress-Strain curves in static loading conditions, we know the stress in force/cross-sectional area that's needed to deform a material. So with a bigger specimen, there's also a bigger cross-sectional area so you need a bigger force to generate the necessary stress. This same concept should...

Hello, I have seen some pictures about hydraulic fracturing, which is injecting water into the ground under high pressure, and when people draw the schematic, it looks like this I am wondering why the fracture will be branched. Thanks!

This is a bit of a multi-part question on impact engineering and FEA usage. I am working on making my Alumina ceramic model as accurate as possible in ANSYS for impact simulations. But I am noticing a common theme, while using model parameters in scientific journals I am not getting any...

Toughness is defined as ability of material to absorb energy when deforming before fracture. Materials with high ductility and strength will have high toughness. What is meant by ability of material to absorb energy? What is connection between strength, ductility and ability to absorb energy so...

How did you find PF?: Google search How we can differentiate failure and fracture using Stress Strain Curve [Mentor Note -- thread moved from the New Member Introduction forum]

Hello everybody We saw a fracture in a switch rail, now we're trying to find the reason, may be you can help us. This rail is made of R260 steel. Let me know if any other information is needed. I have attached pictures of this rail. Thanks in advance

I've been giving this some thought. It's clear that the stiffners will increase the resistance of the material so that the energy release is no longer high enough to cause further fracture. I'm just not sure what formula I can use to take into account the new resistance. I suspect part 1 of the...

(If this is posted in the wrong area, please feel free to move it.) If I take Scotch tape (using the product name), pull out a long strand and then, beginning at the free end, tear it down along its length (to get two strips of the same length, but thinner), the "fracture" (if I may call it...

My question here is regarding fracture of materials. I have problems in understanding some concepts. Now, for static loading, there is a property called KIC (fracture toughness). By equating our stress from the static load to this KIC, we get the maximum length of the crack which does not...

Why are materials whose yield stresses are highly strain-rate dependent more susceptible to brittle fracture than those materials whose yield stresses do not exhibit marked strain-rate dependence

Will, I have weird question , when the glass is broken for example, its take some shap like So Why this happen , I mean if i throw a ball on glass does the weakest place are broken ,does this right?

I'm trying to talk science to anthropologists and hope an academic physicist will let me quote him. Here is the data and my purpose is to prove that wood can't slice a skull the way a sword does . good grief ... " On this basis, the boomerang is the most probable candidate for the main trauma...

I had posted this in the General Engineering forum but perhaps it is a better question for mechanical engineering forum: 1) Consider a centre crack specimen subjected to a wedge load a shown in the figure: https://www.physicsforums.com/attachments/centre_crack_wedge_load-jpg.112584/ In such a...

Seriously, why? Bone is a composite, of apatite that provides rigidity and collagen which provides toughness. Bones of children are soft. They do fracture under excessive forces, but are liable to greenstick fractures. So soft bones of children may deform plastically, as in rickets. Both...

Let's assume I have a large block of crystalline diamond, with reported compressive strength of 110 GPa. If the cross-sectional area of the block is 1 m2, then obviously if I apply a force of 110x10^9 N the material will begin to fracture. But what if the pressure of 110 GPa is applied locally...

Is it true that quenching will decrease the toughness of material and tempering the quenched material will then increase the toughness? I need an explanation in term of the effect of quenching and tempering on the structure of the material.

I have recently been fortunate and clumsy enough to suffer an acute injury leading to a break in my foot which ultimately might be diagnosed today as a "Jones Fracture". The demeanor of the AP that treated it last week was less than reassuring. Anybody have any anecdotal contributions of...

My tutor only knows how to do it with APDL and I seek for a more up to date Workbench solution. How do I evaluate stress concentration factor for a surface plate with a fracture going straight through it (like a slit - no crack width, only length)?

Homework Statement When the thigh is fractured, the patient's leg must be kept under traction. One method of doing so is a variation on the Russell traction apparatus. If the physical therapist specifies that the traction force directed along the leg must be 25N, what must W be? Homework...

I am looking to determine fracture toughness for aluminium, from a punch test. I have the dimensions of the specimen and the load-displacement curve of the test. I have seen how to calculate Kic for brittle materials from a punch test but am struggling to find a formula for ductile materials...

Homework Statement Brittle materials as glass and ceramics have generally a much lower tensile strength than compressive strength. A rigid mass impacts the end of a bar (free-free) of such a material and a piece of the other end drops off. Is there a relation between the length of the piece...

Homework Statement [/B] A tensile load F is to be applied to a tie bar. The tie bar is 50 mm diameter. The surface of the bar has defects resulting from the manufacturing process, these have a maximum depth of 1.5 mm and have a shape factor of 1.4. If the fracture toughness of the material...

When a bolt is pulled in tension and eventually fractures, is all the built up strain energy dissipated in the formation of the new surfaces? Does any energy do into accelerating the broken halves of the bolt? Imagine that two plates are bolted together. As the two plates are forced apart...

I don't know if this is the right forum to be asking this question... Please feel free to redirect me if not. I want to calculate how far a fracture can propagate as part of a project I'm doing. The system is not so simple and I have never dealt with stress analysis and fracturing before. I...

Material: PVC E-modulus: 1300 N/mm^2 Poisson's ratio: 0.35 Applied shear force: 100 N Resisting area: 28 mm^2 Shear modulus: E = 2G(1+v) --> G = E/(2(1+v)) = 1300/(2(1+0.35) = 481 N/mm^2 Does this mean that a force which can be applied to the area without fracturing is 481 N/mm^2 * 28 mm^2? I...

Homework Statement Falls result in hip fractures are a major cause of injury and even death to the elderly. Typically, the hip's speed at impact is about 2.0 m/s. If this can be reduced to 1.3 m/s or less, the hip will usually not fracture. One way to do this is by wearing elastic hip pads. If...

Polycarbonate fracture toughness? I am doing a project in which I have to make a cd case out of a material which is transparent, has a young's modulus not too different to polystyrene, can't cost more than twice polystyrene and has a fracture toughness better than polystyrene! Polycarbonate...

Homework Statement The question is: calculate the total amount of strain at fracture? How much of this is recoverable strain? Explain your answer Homework Equations strain = (change in length)/ (initial length) The Attempt at a Solution I'm not sure about my answer but i just...

Hiii heeeeeelp please. I am new here and hope to find a solution and an easy to understand explanation to my problem:confused:. Thank you all :smile: a. A specimen corresponding to a finite plate of width W = 65 mm is made from a steel with a yield strength of 650 MN m^-2 and contains an edge...

Hi. At what temperature range can brittle fracture be expected in low carbon steels? Are there other parameters which govern its occurance? Thanks.

Hi, why does fracture toughness decrease when a material increases in strength? How do one explain this relationship? Does it have to do with stress vs. strain curve? Thanks.

Reference is to the formula for stress intensity factor : K_I(mode I) = beta*nominal stress*(pi*crack dimension)^1/2 now the question is that 1.ductile: if I use the value of fracture toughness K_c in place of K_I and yield strength in place of nominal stress what will the value of...

The Question I'm Trying to Solve Is: Aluminum alloy (7075-T651) is used for aircraft wing. The largest flaw size monitored in the wing was 9mm. What is the maximum allowable loading so that any catastrophic failure can be avoided? The fracture toughness of aluminum is 26MPa*m^0.5. Assume the...

Homework Statement i have been told i can use the equation potential energy/cross sectional area to work out fracture energy of ice after dropping weights on it till it breaks. is this true? Homework Equations fracture energy = potential energy/cross sectional area The Attempt at a...

Hello, What is the general differences betwen the ASTM E399-09 method and the BS 7448 method? Thanks, Alexisonsmith

\frac{2i}{2+i} i don know how to separate the complex and imaginary part of this fracture?

Homework Statement I am given the trends for yield stress and fracture toughness as functions of temperature for steel. I need to explain the trends Homework Equations none The Attempt at a Solution I am guessing the yield stress is the stress that the material can withstand...

Metals with what type of crystal lattice less prone to brittle fracture? Why?

I am having trouble understanding where the units to fracture energy come from when worked out with the following equation. 2\gamma_{ef}=\frac{K^{2}_{Ic}}{E} fracture energy = fracture toughness/young modulus i asked my teacher as this is part of my coursework but he was not able to...

True or false: a large plate of a brittle material fractures at a higher applied tensile stress as compared to a small plate of the same material. and True or false: the critical stress for a fracture of an internal crack of length 1mm is less than the critical stress for fracture of the same...

Homework Statement A 20.0 meter long uniform beam weighing 820 N rests on walls A and B, as shown in the figure a)Find the maximum weight of a person who can walk to the extreme end D without tipping the beam. b)Find the force that the wall A exert on the beam when the person is...

1. A 19.0 kg ball is supported from the ceiling by rope A. Rope B pulls downward and to the side on the ball. If the angle of A to the vertical is 22 degrees and if B makes an angle of 53 degrees to the vertical find the tension in rope A and then find the tension in rope B

A beam with dimensions 10x10x50mm is loaded in it's middle with a load F and it's supported by two wedges at either end Given it's fracture toughness say 500MPa, what is the largest load that it can hold? I am assuming that the underside of the beam will go into Tension and to calculate...

\frac{1}{x^3(x^2+1)}=\frac{ax^2+bx+c}{x^3}+\frac{dx+e}{x^2}\\ ax^4+bx^3+cx^2+dx^4+ex^3=x^4(a+d)+x^3(b+e)+cx^2=1\\ c=0\\ b+e=0\\ a+d=0\\ i got 4 variables with 2 equations what to do??

I am having difficult finding the meaning of the term 'fracture strength'. http://en.wikipedia.org/wiki/Flexural_strength" it means the flexural or bending strength but that is unsourced and marked as dubious. I was also wondering if it could be synonymous with fracture toughness or something...

what actually causes polymers, ceramics and metals to fracture in either of these ways? From what I understand, polymers can be either brittle or softer which has to do with whether they are thermoset or thermoplastic, saturated or unsaturated, long chain or short chain, etc. but what makes...

Hi all, I'm a 1st year (first 2 weeks) engineering student, with a quick question in regards to fracture points of materials. We're currently going through the elastic modulus and the deflection formula, which is pretty handy and I think I've got a decent (basic) grasp on it now...

I am curious if anyone here is familiar with ABAQUS and using it for crack propagation. I am doing a project on fatigue life and need to use a computer program (ABAQUS is our FEA) to predict fatigue life under specific loading conditions. I am planning to use crack propagation to do this and...

Energy required to "fracture" a planetary mass I was playing around with the Impact Effects calculator at http://www.lpl.arizona.edu/impacteffects/ and doing some thinking about the impact event scenario of the Moon's creation. The main bulk of the Earth seems to have stayed in one piece after...