# 潜在材料失效分析

## 失效准则

Note: 合适的失效准则取决于材料和应用。它还能够反映被认为适合特定设计的保守程度。虽然为每种 SimSolid 材料提供了默认准则，但它们仅应被视为示例。最终决定使用哪种准则是设计工程师的责任。

## 失效理论

CAUTION:

SimSolid 中可用的失效理论如下：

(1)


## 失效准则公式

Table 1.

${\text{τ}}_{\text{max}}\text{=}\text{\hspace{0.17em}}\text{maximum}\text{ }\text{\hspace{0.17em}}\left(\left|\frac{{\sigma }_{1}-{\sigma }_{2}}{2}\right|,\left|\frac{{\sigma }_{2}-{\sigma }_{3}}{2}\right|,\left|\frac{{\sigma }_{3}-{\sigma }_{1}}{2}\right|\right)$

${\text{SF}}_{\text{i}}\text{\hspace{0.17em}}\text{=}\text{\hspace{0.17em}}\frac{{\text{σ}}_{\text{compressive}\text{ }\text{yield}}}{{\text{σ}}_{\text{i}}}$ 如果 ${\text{σ}}_{\text{i}}$ < 0，i = 1, 2, 3

$\text{SF}\text{\hspace{0.17em}}\text{=}\text{\hspace{0.17em}}\text{minimum}\text{\hspace{0.17em}}\left({\text{SF}}_{\text{1}}\text{,}\text{\hspace{0.17em}}{\text{SF}}_{\text{2}}\text{,}\text{\hspace{0.17em}}{\text{SF}}_{\text{3}}\right)$

${\text{SF}}_{4}\text{\hspace{0.17em}}\text{=}\text{\hspace{0.17em}}\frac{1}{\sqrt{EQ}}$

$\text{SF}\text{\hspace{0.17em}}\text{=}\text{\hspace{0.17em}}\text{minimum}\text{\hspace{0.17em}}\left({\text{SF}}_{\text{1}}\text{,}\text{ }{\text{SF}}_{\text{2}}\text{,}\text{ }{\text{SF}}_{\text{3}}\text{,}\text{ }{\text{SF}}_{\text{4}}\right)$

$\text{EQ}\text{\hspace{0.17em}}\text{=}\text{\hspace{0.17em}}\left(\frac{\text{1}}{{\text{σ}}_{\text{tensile}}}\text{ }\text{-}\text{ }\frac{\text{1}}{{\text{σ}}_{\text{compressive}}}\right)\text{\hspace{0.17em}}\left({\text{σ}}_{\text{1}}{\text{+σ}}_{\text{2}}{\text{+σ}}_{\text{3}}\right)\text{\hspace{0.17em}}\text{+}\text{\hspace{0.17em}}\left(\frac{\text{1}}{{\text{σ}}_{\text{yield}}{\text{σ}}_{\text{compressive}}}\right)\text{\hspace{0.17em}}\left({\text{σ}}_{\text{von}\text{ }\text{Mises}}{}^{\text{2}}\right)$