SRC Forum - Message Replies
Forum: Reliability & Maintainability Questions and Answers
Topic: Reliability & Maintainability Questions and Answers
Topic Posted by: Reliability & Maintainability Forum
Organization: System Reliability Center
Date Posted: Mon Aug 31 12:47:36 US/Eastern 1998
Posted by: Michael Moriarty
Date posted: Thu Mar 11 18:59:37 US/Eastern 1999
Subject: Kapton insulated flexible circuits
Does anyone have information regarding the fielded or predicted reliability of Kapton (polyimide) insulated flex circuits. Our potential airborne application is with a "twist-flex capsule" in a turret assembly. Please note the distinction between flexible circuit and lead wire. I'm well aware of the widely documented "arc tracking" failure mechanisms associated with bundled Kapton-insulated lead wire on aircraft. My goal is to assess the probability of arc tracking occurring with single layered flex circuits, not lead wire. Any help would be appreciated.
Subject: Evaluation of the Twist-flex Capsule
Reply Posted by: Mark Mobley
Organization: Baker Hughes Inteq
Date Posted: Tue Mar 23 11:21:31 US/Eastern 1999
You have two sure options: 1. Check the manufacturer's data, if its not sufficient you are forced into the 2nd option,
2. Build a test/evaluation fixture and find out. You should try to duplicate the "use environment" as much as possible.
It maybe possible to accelerate the evaluation using a higher temperature (only if you have an acceleration factor assoicated with breakdown at temp.) Have fun.
Subject: Kapton Reliability
Reply Posted by: Bruce Dudley
Organization: Reliability Analysis Center
Date Posted: Mon Apr 5 12:40:24 US/Eastern 1999
The Reliability Analysis Center does not have any specific failure rate data for Kapton Polyimide flex circuits. The information available indicates that polymides dielectrics have excellent temperature resistance, very good chemical resistance, good electrical properties, vey good adhesion, fair flexibility, poor moisture absorption and high cost.