Can we define material property in Tabled Type of Fatigue?

Altair Forum User

I know we can set material property of fatigue in MATFAT.

And we can set the SN curve points of the material.

I am curious about can we use the TABLE's type to import our material data in fatigue material?

Because at the thermal we can do for this.

<?xml version="1.0" encoding="UTF-8"?>

And I also have problem about the FATPARM's instruction of COMBINE

what is 'SG' mean? Because I have seen it shown like the photo and it also written in SGVON (SG von-Mises)

image.png.425b1c918353cb968cce88ad8d9283ad.png

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Altair Forum User

I know we can set material property of fatigue in MATFAT.

And we can set the SN curve points of the material.

I am curious about can we use the TABLE's type to import our material data in fatigue material?

hi,

Do you mean non-linear material?

Von Mises alone is strictly positive. So, if you are referring Vonmises for fatigue analysis only positive history is taken into account. Whereas signed-von Mises can take both negative and positive. Same with Tresca

Altair Forum User

@Prakash Pagadala Thanks to your reply.

Here I mean the define SN in MATFAT can we set the SR1 or B1 in TABLE's type?

And here I know the SG is means we have both positive and negative.

Altair Forum User

Hi,

You can define a SN curve using TABLEXN in which X will be stress and Y will Life.

Nathan_22110

Hi,

You can define a SN curve using TABLEXN in which X will be stress and Y will Life.

@Prakash Pagadala Thanks to your reply.

Here I mean the define SN in MATFAT can we set the SR1 or B1 in TABLE's type?

And here I know the SG is means we have both positive and negative.

Hi,

I had the same problem a few minutes ago. In OptiStruct help it was well explained that you can use TABLEXN to define manually one S-N curve, and that you can also use SNCM continuation line with FATMCRV card to define multi-mean SN curve. I found these options in HyperMesh 2019.1 but not in 2017.3.

So, I wonder if there is a way to define one SN curve with that version other than using SRI1/b1 coefficients, in other words if there is a way to define an SN curve manually. Because I am able to create a FATMCRV Load collector, but there isn't any SNCM continuation line to reference FATMCRv or TABLEXN data.