What is Nylon?

July 29, 2021 5:21 pm Leave a Comment

Nylon is a versatile synthetic plastic fiber used in everything from stockings to toothbrush bristles to industrial wear components. Introduced as an alternative to silk in the 1930s, the plastic is a long, heavy chain of repeating polymer patterns—including diamine acid and dicarboxylic acid—known for its easy combination with other materials. Depending on which material a manufacturer chooses to mix it with, nylon can take on a broad range of properties and textures. This capability makes nylon well-suited for creating durable engineering plastics.

Properties & Benefits of Nylon

While the specific properties of any nylon depend heavily on the other materials involved, there are a few key properties and benefits that the inclusion of nylon imparts to the plastic material. Some of the most common properties include:

Strength and toughness. Nylon boasts incredible strength and material toughness, which brings a host of benefits to applications in a variety of industries. For example, nylons are regularly used to reinforce rubber vehicle tires or to make rope.
Dyeable. Nylon is easily dyed, making it ideal when an engineering plastic needs to match a particular brand or aesthetic.
Abrasion resistance. High resistance to abrasion makes nylon a popular choice for producing moving mechanical parts, such as gears, machine screws, or sheaves.

Common Applications for Nylon Plastics

With such a diverse, comprehensive set of features and benefits, nylon is the perfect fit for many potential applications. In addition to consumer-facing applications such as clothing, nylon is also an essential material for many industrial use cases. Some of these include:

Moving Machine Parts

With a low coefficient of friction, nylon is an excellent addition to products that slide or rotate. The material can handle motion without dampening its force or requiring more energy to keep the process going. It’s high wear resistance also enables it to provide a long service life in these scenarios. Specific examples of this principle include:

Sheaves
Wear Pads
Gears
Wheels
Rollers

Sealing, Structural, and Protective Components

Nylon is lightweight, yet durable and stiff. This combination provides a good solution for an expansive range of components, ranging from sealing solutions to building components. Examples include:

Wear pads
Seals and gaskets
Bearings and bushings

Sensitive Machinery Parts

Nylon’s resistance to corrosive elements ensures favorable performance in sensitive applications where machinery must handle organic, perishable, or otherwise fragile components. Relevant industries include:

Packaging machinery parts
Food processing machinery parts

WS Hampshire: Your Customer Fabricator/Supplier of Nylon & Other Nonmetallic Materials

Nylon offers a broad range of material properties that make it suitable for use across numerous industries. Crafting the best possible nylon plastic solution for your particular application requires careful planning and material selection. If you’re looking to take advantage of the durability, resistances, and strength that make nylon an ideal fit for industrial and consumer-facing products, partner with WS Hampshire’s team of experts to get the job done right. We offer custom bearing, bushing, and wear solutions that will help improve the functionality and lifespan of your products.

To see how we can help, please contact us today.

What is FR4 Material?

5:18 pm Leave a Comment

FR4 is a multipurpose glass epoxy laminate that features flame-retardant properties, as indicated by the letters “FR” in its name. It is often the substrate material of choice for electrical insulation, recognizable by its signature green color. The material’s low coefficient of thermal expansion allows it to resist contraction and expansion under exposure to fluctuating operating temperatures, making it ideal for high-temperature applications. FR4’s exceptional dielectric properties also contribute to its capability as an insulator.

FR4 has no moisture absorbing properties, so it will not expand or contract when humidity changes and is not affected by direct exposure to water, making it excellent for marine components.

Properties of FR4

Flame Retardant 4 is a glass epoxy laminate and a defined standard by National Electrical Manufacturers Association (NEMA). It complies with UL94V-0 standards for flame-retardant plastic material. Insulators and structural components made from FR4 with the UL standard marking are guaranteed to prevent fire propagation and extinguish the fire quickly.

The glass transition (Tg) for Flame Retardant 4 lies between 115°C and 200°C, depending on the manufacturing method and resin material. The material gains its fire-resistant properties from the presence of the halogen chemical element bromine. FR4 also features a high strength-to-weight ratio and high hardness, ensuring the material will not break easily under load or during machining.

Common Applications for FR4

While Flame Retardant 4 is well-known for fabricating PCBs, it also provides an ideal material for:

Industrial Wear Applications
Electrical Insulation
Screw Terminal Strips
Transformers
Arc Shields
Washers
Busbars
Standoffs
Switches
Relays

WS Hampshire: Your Custom Fabricator/Supplier for FR4 & Nonmetallic Materials

FR4 is a flame-retardant material used for various components in electronics and industrial or marine applications. Flame Retardant 4 is known for its good dielectric properties and acts as a good insulator for electronics. It withstands high temperatures, temperature fluctuations, and humidity and moisture exposure without expanding or contracting. Flame Retardant 4 can also be machined, making it ideal for use in mass production.

At WS Hampshire, we fabricate and supply FR4 for use in electronics, marine applications, and more. Our CNC machines provide high-precision components with fast turnarounds in any production volume. We can custom-fabricate a range of nonmetallic materials and provide wear solutions, bearings, bushings, plastic forming, and paper and film fabrication.

How to use a Technical Data Sheet.

July 19, 2021 2:48 pm Leave a Comment

COMPOSITE MATERIAL TECHNICAL DATA SHEETS –

WHAT THEY ARE, WHAT THEY AREN’T & HOW TO USE THEM

One of the most frequent request we get is to provide a Technical Data Sheet (TDS) for a given material. But do you know what you are getting, and how to use it?

First – a list of what a TDS is NOT:

“absolute values” – they are averaged values from many data points
“minimum values” – – same comment
“QA values” – these are not “go / no go” values

Technical Data Sheets are a comparative tool that allows you to see the general differences between materials in an organized format and is best used to compare materials from the same source! Many mills use the resin data for their TDS, as it is the “lowest common denominator” – and there is a relatively limited pool of resin suppliers.

All thermoset suppliers (phenolics) and some thermoplastics mills test the actual shapes, but these are averaged. Think about it-cast nylon can be made in .187” or 10” plate – so exactly what is its tensile strength?

Some mills report ranges, technically more correct but makes comparing materials difficult – if one lists tensile is 13,000 – 15,000 psi and the other 14,000 psi, which is better?

Also – there is no direct correlation between ASTM and ISO/DIN values – the test samples and methods are completely different. Within each system, comparisons are usually valid. Information on electrical properties, flammability, etc are always consistent and useful “as is”.

Not knowing the data source can have consequences. An airplane manufacturer specification required its supplier to use PAI rod with a minimum tensile strength of 22,000 psi. Their usual sources told them “in rod, it’s 18,000 psi”. Another source supplied a resin data sheet, listing tensile of 22,500 psi and won the order, but the parts ultimately failed. (NOTE: the key error here was with the airplane company, specifying extruded rod using resin data)

Examples of “data reporting & terminology license” to watch out for:

Heat Deflection Temperature – the ASTM specification says you can run this at 66 psi or 264 psi.
Moisture Absorption – Most mills report 24 hr moisture pick-up, and full saturation values – but some report “equilibrium”, a number always lower than saturation to make the material look more stable than it really is.

Concerned or confused? Don’t be – the material experts at WS HAMPSHIRE can help you get the right information for your application evaluation. You’re in the right place!

Tom Connelly is a self proclaimed “Street Engineer” with over 40 years in the plastics industry.

Material Temperature Ratings- What do they Mean?

July 9, 2021 4:02 pm Leave a Comment

Material data sheets usually list several temperature values – what do they mean, and how do you use them to help select the best material for your application?

These values are different for thermoplastics (defined as materials which can be remelted) and thermosets (materials which are crosslinked and therefore cannot be remelted). Today, we deal with the true thermoplastics.

Melt Temperature

Temperature when a material goes from a solid to a liquid, obviously a “limiting” value!

Glass Transition (Tg) Temperature

Temperature when an amorphous thermoplastic (think acrylic or ABS) becomes soft and rubbery. This feature allows certain resins to be thermoformed, though it can be problematic in service.

Continuous Use Temperature

This value is technically defined as the maximum ambient service temperature (in air) that a material can withstand while retaining 50% of its initial physical properties after long term exposure (100,000 hours, or about 11 years) with no load applied. It’s a function of thermal degradation through oxidation.

Heat Deflection (or Distortion) Temperature

This is the temperature at which a 1/2” thick test bar, loaded to a specified bending stress, deflects by .010″ in under a given load (either 66 psi or [more commonly] 264 psi. This is the “working load” temperature, indicating the limit a material can withstand under load.

(NOTE – “heat stabilized” plastics have an antioxidant added, it can add to Continuous Use Temperature but does NOT help Heat Deflection Temperature!)

So – functionally, what does this mean? Take PTFE (“Teflon®”) – everyone knows it’s a 500F material, but that is continuous use – at about 160F you can push your finger into it (Heat Deflection Temperature).

Some Guidelines

In general, with the lower temperature thermoplastics the Heat Deflection Temperature is at or above the Continuous Use Temperature.
In general, it’s the opposite with the higher performance thermoplastics as the Continuous Use Temperature is higher than the Heat Deflection Temperature (see the PTFE example, above)
Most thermoplastics can withstand short term excursions beyond the values given, as long as the loads are not near the “safe load limits” for the material. When passing the Continuous Use Temperature values – parts usually wear out long before the 11 year thermal degradation means anything.

This last point leads to a discussion on Dynamic Modulus Analysis. This is where viscoelastic materials’ properties change with increases in temperature. That one is a topic for another blog post – stay tuned!