Need Recommendation for high impact strength material

[RRana]

Hello Forum!
I am looking for some hands-on recommendation for a material/s that retains high impact strength between -40 to 65C. A structural frame using the recommended material/s will be designed to be manufactured using injection molding process. This frame needs to support a load of 120 lbs. and be able to take the impact when it is dropped from 10 feet height loaded. One of the main objective is also for it to be as light as possible. Of course, the cross-section of the load carrying members will have bearing on the part weight and strength for it to be a success. We have a 3D model that we want to do an FEA on and be able to do 'What If' scenario using few different recommended materials.
Any insight will be useful and be greatly appreciated. As always, cost has to be as low as possible.

As always, thank you all for your anticipated recommendations.

RR

 

[Demon3]

Cheapest material with good strength and impact resistance is PP. If you need more strength add filler such as glass fiber. If you need more impact resistance than PP homopolymer gives then use PP copolymer. However, you need low temperature impact resistance so PP is out.

Next up is high impact polystyrene. I would choose that unless you need chemical resistance, i.e. to solvents or cleaning agents like Pledge etc..

If you need the chemical resistance then choose ABS instead.

If you need stability outdoors then those solutions won't work and you should try UV stabilized ABS. If that fails (goes brittle) under your required exposure to light then you need to use ASA instead.

Chris DeArmitt PhD FRSC CChem

http://www.phantomplastics.com

Consultant to the plastics industry

 

[RRana]

Thanks demon,
Have you or anyone in the forum had experience using Valox and/or Xenoy for such an application for low temperature impact strength? If yes, what particular formulation of either of these plastic alloy/s did you use? Chemical resistance is not critical as salt water is probably the most likely it will be exposed to.
I am also looking for some goof extruder/s in the mid-atlantic region, any recommendations folks/

thanks once again,
RR

 

[Demon3]

Hi RR,

Those are both types of PBT (a polyester similar to PET). I'm sure the supplier can provide advice. PBT is good outdoors and is used in some automotive parts. To get good impact resistance it will probably need to be an impact modified grade (you add rubber particles to it). In fact I'm giving a webinar tomorrow on impact modification of thermoplastics.

You can search plastics grades free by property at

http://www.matweb.com

All the best,

Chris

Chris DeArmitt PhD FRSC CChem

http://www.phantomplastics.com

Consultant to the plastics industry

 

[Pud]

Well, my list would include:

Impact modified unreinforced nylon*.
Impact modified GF nylon*
Polycarbonate
Impact modifed PBT/PET (Vandar is a trade name)

Note the polyesters, whilst good materials have a high SG and are expensive to start with.

* We use these to make parts for fighting vehicle tracks.

A lot more info is required really - bit like "pin the tail on the donkey" at the moment.

H

http://www.tynevalleyplastics.co.uk

 

[patprimmer]

No where near enough information.

All recommendations above are valid under some circumstances.

Polyester block co-polymers like Hytrel and Arnitel have a good temperature range re impact and are good to well below -40C, however they are expensive and somewhat flexible. From the information supplies I have no idea of what flex mod is required.

Occasionally mouldings are exposed to chemicals that where not considered, from cleaning chemicals to lubricants to droppings or secretions from animals or plants.

Regards
Pat
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[unclesyd]

Depending on your requirements you may want to consider liner materials offered Plastic Lining Solutions

http://www.plasticliningsolutions.com/applications.html

Here is a little information on PE of the UHMW variety. I have used these material in very high impact wear applications with great results.

http://www.astralloy.com/pdf/Linebacker.pdf

http://www.polymerplastics.com/mechanical_uhmw.shtml