FEA and mechnic of materials

Question 1

what is ductile material

Answer 1

failure occurs at the onset of plastic deformation

Question 2

Brittle material?

Answer 2

failure occurs at fractures

Question 3

what is hydrostatic stress?

Answer 3

Hydrostatic stress refers to a type of stress in a material where the stress is applied uniformly in all directions. It occurs when a material is under pressure from all sides with equal force. Unlike other types of stress (such as shear stress), hydrostatic stress does not result in deformation or shape change because the forces are evenly distributed, leading to a change in volume rather than shape.

Question 4

does hydrostatic stress matters for brittle materials?

Answer 4

Yes, but it does not for ductile material

Question 5

which one is more consevative, von-mises or Tresca criteria for ductile materials

Answer 5

Tresca is more conservative while von-mises aligns better for experimental data

Question 6

These materials absorb a lot of energy before failure, making them tough and less likely to fail catastrophically: ductile or brittle?

Answer 6

ductile

Question 7

he fracture surface is usually smooth and flat, indicating a clean break: ductile or brittle?

Answer 7

Brittle

Question 8

what is mesh compatibility?

Answer 8

a continuous model is created with no gap and overlap (all nodes are connected to each other)

Question 9

what is element order in FEA?

Answer 9

The order of elements in FEA determines how the solution is interpolated within each element and has a significant impact on the simulation’s accuracy and efficiency.

Question 10

why are nodal stresses are higher than element stresses?

Answer 10

In finite element analysis (FEA), nodal stresses often appear higher than element stresses because nodal stresses represent specific points where stress concentrations can occur. These peak values arise from the direct influence of stress calculations at nodes, which are susceptible to numerical differentiation errors, mesh quality issues, and the inherent nature of stress interpolation using shape functions. In contrast, element stresses are averaged over the entire element, providing a smoother and more generalized view of the stress distribution

Question 11

What type of analysis a shell model should be used for?

Answer 11

displacement and modal analysis

Question 12

what type of FEA model should be used for stress concentration?

Answer 12

Solid models (elemnts)

Question 13

in Solidworks, what is immovable fixture used for?

Answer 13

for just removing translational dof (hinge boundary condition)