## General Mechanical

#### In workbench, how to obtain plastic work density

• b.x. Yang
Subscriber
In workbench, user defined result, such as 'volum' and 'nlplwk' can acquire element volume and nodal plastic work. Using the two outcomes, plastic work density may be obtained, theoretically.nI've tried, but finding that It's just a numerical result. It can't tell me where is the critical region.nSo I wander whether there is an handy way telling me where is the region with biggest plastic work density.nn
• Sean Harvey
Ansys Employee
Hello, so nlplwk is the non-linear plastic work per unit volume. nl does not indicated nodal. This quantity already has the volume accounted for, so no need to do anything further. It can be compared to the modulus of toughness of a material. If you do a search on modulus of toughness you will find detailed explanation. So this can be used to get a sense of how much strain energy per unit volume the material can withstand before fracture. It can also be used in fatigue applications and with solder that can be common.nSo if you make a contour plot you can see the contour of value and you can compare it to the modulus of toughness. Let us know if this answers your question.nnThank younSann
• b.x. Yang
Subscriber
thank you very much.nNLPLWK means plastic work divide element volume, is that right? nMy another question is the unit. If I choose ?MKS unit system in ANSYS Workbench, result from NLPLWK represents pJ/?m^3, also 10^6 J/m^3?n
• florian.gautron
Subscriber

Hi, I wanted to know : For a thermal cyclic simulation, as NLPLWK is the non-linear palstic work per unit volume, if I plot the stress (SXZ) function of the strain (EPPLXZ) for an element for one cycle, the area inside the hysteresis that I obtained plotting this curve has to be equal to the NLPLWK that was calculated for this element right ?

I can't find the same results...

Can you tell me how the NLPLWK is exactly calculated please, so i can figure out how to correlate it with SXZ and EPPLXZ ?