enghard
Mechanical
- Dec 28, 2006
- 5
Hi,
I am redesigning an existing part for lower cost.
The most promising material that fits the bill is Ticona’s Fortron 1140L4 (40% glass fibre reinforced). I’m designing for injection molding. The part will be in contact with hot (90C) ethylene glycol and also has to withstand considerable stress levels. My problem is that I don’t know enough about the deterioration of the mechanical properties after long-term exposure to hot ethylene glycol. The required operational lifetime is 5000 h.
Previous accelerated stress testing done in-house indicated that yield and ultimate strengths fall sharply within the first 700 h, continuing to decrease just slightly after that. This test was terminated after 2500 h.
Would it be good practice to extrapolate the curve to 5000 h, or can I expect the curve to “tank”? I’m trying to prevent a test repeat.
Has anyone performed similar tests that would give me the peace of mind that Fortron 1140L4 could safely be used?
I’m also open to other material suggestions.
Thanks
I am redesigning an existing part for lower cost.
The most promising material that fits the bill is Ticona’s Fortron 1140L4 (40% glass fibre reinforced). I’m designing for injection molding. The part will be in contact with hot (90C) ethylene glycol and also has to withstand considerable stress levels. My problem is that I don’t know enough about the deterioration of the mechanical properties after long-term exposure to hot ethylene glycol. The required operational lifetime is 5000 h.
Previous accelerated stress testing done in-house indicated that yield and ultimate strengths fall sharply within the first 700 h, continuing to decrease just slightly after that. This test was terminated after 2500 h.
Would it be good practice to extrapolate the curve to 5000 h, or can I expect the curve to “tank”? I’m trying to prevent a test repeat.
Has anyone performed similar tests that would give me the peace of mind that Fortron 1140L4 could safely be used?
I’m also open to other material suggestions.
Thanks