Hello ladies and gentlemen! I could use some diverse minds to help me solve a problem with a potentially life saving piece of equipment. I am looking for a material that is lightweight, cost effective and has good anti-ballistic property's. I work in an environment where knifes and ice-pick are a greater threat then bullets. After a close call and armor failure, I am needing something better.

 

I am playing with the idea of making a flexible roman reminiscent lamellar armor .I am currently working with Kevlar, HDPE specify delrin (polyethylene high-density) , Fiberglass (resin coated) ,vulcanized rubber, aluminum and PVC sheeting. My goal is to make round laminated disc to stack and intertwine with dyneema cord.If you are aware of any materials that could help me that is cost effective, please let me know. This is my first post here. Any input will be greatly appreciated! Sorry if I didn't follow correct posting protocol. I figured the most appropriate place for this was under physics or possibly engineering.

 

What the vest is up against: "The ice pick has a 4 mm (0.16 in) diameter with a sharp tip with a 5.4 m/s (17 ft/s) terminal velocity in the test."(wikipedia.org/wiki/Ballistic_vest)

Edited July 4, 201213 yr by ForScience!

Kevlar will not stop an ice pick even in thicknesses used in bullet-resistant vests.

A plate of HDPE thick enough to stop the pick will be heavy, uncomfortable and limit mobility.

Empregnated fiberglass will not stop penetration of a pick any better that the first two.

Rubber is better at preventing penetration but the weight and rigidity of it at appropriate thicknesses would limit mobility.

Aluminum sheet is rigid but could be used to protect vitals or used as scales could solve all but the weight concern.

PVC is brittle and rigid - again the weight of it in appropriate thickness would limit mobility

 

Front and back plates along with neck and face protection is likely to be a good add-on.

Lexan (or other name brands of similar polycarbonate) are candidates in the same range as other rigid materials.

 

A heavy leather jacket and well placed 1/8" Lexan sheets that overlap would be as good as anything against an ice-pick.

 

Paul

I would want a very fine chain mail, it prevents sharks from biting, add a infusion of polycarbonate and a layer of kevlar mesh and it should be quite effective.

The chain mail weighs over 25 pounds, a Kevlar vest is 20 pounds and depending on how much poly-carbonate you use it is denser than Kevlar.

Shark's teeth are triangular, the ice-pick is a round rod. Chain mail won't work. Kevlar is worthless against a pick. The poly is good for stopping the penetration of a sharp object but it has to be a minimum thickness (somewhere near 1/8"). To keep it flexible the poly would have to be multiple layers of scales and it would then be very heavy.

The chain mail weighs over 25 pounds, a Kevlar vest is 20 pounds and depending on how much poly-carbonate you use it is denser than Kevlar.

Shark's teeth are triangular, the ice-pick is a round rod. Chain mail won't work. Kevlar is worthless against a pick. The poly is good for stopping the penetration of a sharp object but it has to be a minimum thickness (somewhere near 1/8"). To keep it flexible the poly would have to be multiple layers of scales and it would then be very heavy.

 

 

It would depend greatly on how small the mesh was and how thin the sharp object was, chain mail should stop a knife quite handily, a very fine mesh impregnated with plastic and a layer of kevlar fiber should have some stopping power. Not all shark teeth are triangular but they are not round rods either...

 

Possibly the person being attacked should just shoot the bastard... Just kidding, this is a difficult thing to engineer, there is a need for a needle proof glove in medicine, very difficult to achieve as well...

 

The polycarbonate scales looks like a good direction to go. Polycarbonate scales over a kevlar layer might do both jobs, stopping bullets and sharp objects...

Thank for all the feedback! I am making tester disc to find which can hold the greatest psi vs weight and thickness. I am liking the results of this in

layers :ballistic nylon outer layer, 1mm delrin, 2 peices of kevlar, anti puncture rubber sheet, then 1mm delrin with high density felt for comfort.

 

With this I maxed out my testing rig. I have even considered seeing if it is bullet resistant. I have not settled on disc size.

Edited July 16, 201213 yr by ForScience!