Inventor FEA Safety Factor Questions

[robert.martinZMNUD]

Hi, I have a question regarding how to interpret Inventor FEA results. 
The part attached below is a rack meant to support a max load of 7000kgf, and I've dictated as such within the analysis. 
Upon reviewing the calculated results, I've noticed that in a certain area of the part ( where the support box sections meet the feet of the rack ) there is a safety factor of 0.69. 
When referencing the Von Mises stress in the area against the materials Yield and Tensile Strengths, I can see that it exceeds the Yield Strength, but not the Tensile Strength. 
I've taken this to assume that yield will occur, but no evidence of deformation is present according to Inventor's FEA results. As such, I'm not exactly sure how to interpret these results. ?
Does this mean the part will break under the specified load? Or is something else occuring?

[JDMather]

An assembly must include parts.

Static linear elastic stress analysis is not a measure of fracture (refer to a standard stress/strain graph.

I would probably use Frame Analysis (beam elements) rather than tetrahedral mesh elements for an assembly like that.

[robert.martinZMNUD]

Thank you for the quick reply.
You're right, I forgot to include the 3D Sketch, I've added it in. Do I need the frame parts as well? 
Also, I've just tried running it on Frame Analysis. Is there a way to input a single 68646N (7000kg) Force and have that be distributed across the middle beam? 

[JDMather]

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@robert.martinZMNUD wrote:

 Do I need the frame parts as well? 

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Yes.

The usual process is to right click on the project folder and Send to Compressed (Zipped) Folder and attach the resulting *.zip file here.  (Or use Save Copy As> Pack and Go.)

[robert.martinZMNUD]

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@JDMather wrote:Yes.

The usual process is to right click on the project folder and Send to Compressed (Zipped) Folder and attach the resulting *.zip file here.  (Or use Save Copy As> Pack and Go.)

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Will this do?

[JDMather]

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@robert.martinZMNUD wrote:

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@JDMather wrote: Yes.

The usual process is to right click on the project folder and Send to Compressed (Zipped) Folder and attach the resulting *.zip file here.  (Or use Save Copy As> Pack and Go.)

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Will this do?

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No, I do not own a RAR extractor on my clean Inventor machine.  I have only Windows OS to zip files.

I have started over recreating your skeleton sketch from scratch.  (see Attached)

Note that it is fully constrained, no duplicate dimensions, was easier to create than a 3D sketch.

[robert.martinZMNUD]

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@JDMather wrote:

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No, I do not own a RAR extractor on my clean Inventor machine.  I have only Windows OS to zip files.

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Apologies, this should work then.

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@JDMather wrote:

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Note that it is fully constrained, no duplicate dimensions, was easier to create than a 3D sketch.

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You're right, I could create the skeleton with two 2D Sketches instead. Is fully constraining your sketches not a standard practice?

[robert.martinZMNUD]

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@JDMather wrote:

Static linear elastic stress analysis is not a measure of fracture (refer to a standard stress/strain graph.

I would probably use Frame Analysis (beam elements) rather than tetrahedral mesh elements for an assembly like that.

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It looks as though Frame Analysis doesn't give you Von Mises stress or Safety Factor results, am I correct in assuming this? 
The reason I've been running it in standard FEA is that, aside from being more familiar with it, it is important to the scope of my work that we acquire the safety factors for each model created. Hence my attempting to interpret the results shown here. 
In referencing standard stress-strain graphs, I can see that it's yet to undergo the necking process, and would still be in strain hardening. As I understand it, any Safety Factor below 1.0 is unacceptable for industrial purposes, but I'm curious as to how viable the part would be in a regular real world scenario. Would it still be able to serve its function without eventually breaking apart?

[robert.martinZMNUD · Accepted solution]

I have since redesigned the assembly in question in order to produce an acceptable safety factor. 
Additionally, although the area of concern may not fracture entirely, there will be some degree of deformation and strain hardening and I have thus taken to assume that the part will fail eventually.