Metal Materials

Common Metal Materials
Aluminum 6061 This is the most common general purpose aluminum used for CNC machining. The main alloying elements are magnesium, silicon, and iron. Like all aluminum alloys it has a good strength-to-weight ratio and is naturally resistant to atmospheric corrosion.
Other advantages of this material are that it has good workability and CNC machinability, can be welded and anodized, and its wide availability means that it's economical.
6061 is a material that's typically used for auto parts, bicycle frames, sporting goods, some aircraft components, and frames for RC vehicles.
Aluminum 70757075 is a higher grade of aluminum, alloyed mainly with zinc. It's one of the strongest aluminum alloys used in machining, with excellent strength-to-weight characteristics.
7075 is also machinable and can be anodized.
We routinely use 7075 T6 for making plastic injection mold tools. It's also used for high-strength recreational equipment for mountain climbing, as well as for automotive and aerospace frames, and other stressed parts.
Brass is an alloy of copper and zinc. It's a very soft metal, and can often be machined without lubrication. It's a material that's also highly workable at room temperature, so it often finds applications that doesn't require great strength. There are many kinds of brass, largely depending on the percentage of zinc. As this percentage increases, corrosion resistance decreases.
Brass takes a high polish that looks much like gold.
Is common in plumbing fittings, home decorative hardware, zippers, naval hardware, and musical instruments.
Magnesium AZ31
Magnesium AZ31 is an alloy with aluminum and zinc. it is up to 35% lighter than aluminum, with equivalent strength, but it's also a bit more expensive.
Magnesium is a material that's easy to machine but it's very flammable especially in powder form, so it must be machined with a liquid lubricant. Magnesium can be anodized to improve its corrosion resistance. It's also highly stable as a structural material and is an excellent choice for pressure die casting.
Magnesium AZ31 is often used for aircraft components in which light weight and high strength are most desirable, and can also be found in the housings for power tools, laptop cases and camera bodies.
Stainless Steel 303
There are many varieties of stainless steel, so called because of the addition of chromium that helps to deter oxidation (rust).
303 isn't a good choice for cold forming (bending), nor can it be heat treated.       The presence of sulfur also means it's not a good candidate for welding. It does have excellent machining properties but care must be taken with speeds/feeds and the sharpness of cutting tools.
303 is often used for stainless nuts and bolts, fitting, shafts, and gears. It should not, however, be used for marine grade fittings.
Stainless Steel 304
This is the most common form of stainless steel found in a wide variety of consumer and industrial products. Often called 18/8, this refers to the addition of 18% chromium and 8% nickel to the alloy.         These two elements also make this machining material especially tough and non-magnetic.
304 is a material that is readily machineable, yet unlike 303 it can be welded. It's also more corrosion resistant in most normal (non-chemical) environments. For machinists, it should be processed with very sharp cutting tools, and not contaminated with other metals.
Stainless Steel 304 is an excellent material choice for kitchen accessories and cutlery, tanks, and pipes used in industry, architecture, and automotive trim.
Stainless Steel 316 The addition of molybdenum makes 316 even more corrosion resistant, so it's often considered a marine-grade stainless steel. It's also tough, and easy to weld. Marine grade stainless steel shackle 316 is used in architectural and marine fittings, for industrial pipes and tanks, automotive trim, and kitchen cutlery.
Carbon Steel 1045This is a common grade of mild steel, i.e., not stainless. It's typically less expensive than stainless steels, but considerably stronger and tougher. It's easy to machine and to weld, and it can be work hardened and heat treated for various hardnesses. 1045 steel (in the European standard, C45) is used in many industrial applications for nuts and bolts, gears, shafts, connecting rods, and other mechanical parts requiring a higher degree of toughness and strength than stainless. It's also used in architecture, but if exposed to the environment it will usually be surface treated to prevent rust.
More materials CFRP, CRP, CFRTP. AL 1050. AL 1060. AL 2024. AL 5052-H11. AL 5083. AL 6061. AL 6082. AL 7075. AL + Br. AL – MIC-6. AL QC-10. Cu + Zn. Cu. Cu + Be. Mg. Cu + Sn + P. SS 303. SS 304. SS 316. SS 410. SS 431. SS 440. SS 630. SS 1040. SS 45. SS D2. Tin bronze. Titanium Ti.Titanium alloy. Zinc Zn

Plastic Materias

Common Plastic Materials for CNC Machining

Plastic resins used for CNC milling and turning must be rigid enough to hold their shape while they're clamped in a vise or fixture. That's one consideration that narrows the field of available materials. The following types of plastic resin have proven themselves over the years because they are stable, strong, easily machined, and produce great finished parts and prototypes.

ABS ABS is an excellent choice for CNC machining. ABS is a tough, impact-resistant plastic that's also resistant to chemicals and electrical current. ABS is easy to color so it produces good cosmetic results. Because of its versatility and strength, it's the most common plastic that we use for rapid prototyping. You'll find it in automotive components, power tools, toys and sporting goods, among many other applications. ABS is less expensive than other engineering plastics like PEEK or Ultem but it doesn't withstand high temperatures for long periods of time.
NylonNylon has many of the same desirable characteristics as ABS. It has greater tensile strength which is why we use it for fabric and rope. Nylon and ABS resins are often mixed together, along with glass fibers, to enhance their desirable properties. Nylon can replace many mechanical parts, and because it has good surface lubrication it's used for moving gears and sliding components. One drawback to nylon is that it does absorb moisture over time so it's not suitable for marine applications. And it can be tough on cutting tools during machining.
Acrylic PMMA is a rigid, transparent resin used as a substitute for glass or when making other clear optical parts. It resists scratching but is less impact resistant than polycarbonate. One advantage of PMMA is that it doesn't contain Bisphenol-A, so it can be used for food storage. After machining, acrylic shows a hazy, matte surface. The surface can be treated with vapor polishing, which we do at Star Rapid, to make it optically clear. One thing to be aware of about acrylic is that it's susceptible to heat deformation, so it should be stress-relieved before machining. PMMA is used for display screens, light pipes, lenses, clear enclosures, food storage, and to replace glass if strength is not an issue.
PEEK is a true high-strength and stable engineering plastic. It can be used as a substitute for metal in many applications and it can withstand prolonged exposure to high temperatures. PEEK is used for advanced medical, aerospace, and electronic components. It's also a great choice for lightweight fixtures because it doesn't tend to creep, or deform, over time like other resins. PEEK is much more expensive than many other plastics so it tends to be used only when nothing else will do. In many cases, it's necessary to anneal it during the machining process, or else it will form stress fractures.
More materials ABS. ABS + PC. HDPE, PEHD. PA6. PA6 + 30% GF. PA66 + 30% GF. PA66. PBT. PC. PC + GF. PC + 30 % GF. PEEK. PEI. Ultem 1000 + 30% GF. Ultem 1000. PE. PET. PMMA – Acrylic. POM. PPS. PPS + GF. PPSU. PP. PTFE. PVC…

Common Plastic Materials for injection molding maerials

We often get asked what the best plastic injection molding resin is to use for certain projects. And honestly there is no one answer for that. The best resin is the one that works for you and your unique circumstances.
When choosing a plastic, the first thing you have to consider is the part's function and the physical environment that it's going to be exposed to. So clearly you'll need to consider what type of injection molding material is going to stand up to various environmental challenges such as temperature fluctuations, moisture, chemical exposure, UV light, and many more. Then the material's strength, durability, flexibility, color, and cost come into play. Therefore, we'd like to help you refine your search by explaining the properties of the ten most common plastic injection molding resins .

Acrylonitrile Butadiene Styrene
An image of ABS computer keyboard keys. This shows one of the most common applications for this type of plastic. ABS resin is an opaque thermoplastic polymer and an engineering grade plastic. There are many advantages to using ABS. It's tough, has good dimensional stability, it resists impacts and scratching, and is hard to break.Also, the low melting temperature makes it easy to mold. It's commonly used to produce electronic parts such as phone adaptors, keyboard keys, and wall socket plastic guards. Why is this? Because ABS is a good insulator and won't conduct electricity or give off fumes if it's exposed to fire. These are important considerations for product developers working on electrical devices.
An image of a red polypropylene bottle cap, showing the live hinge detail.This thermoplastic injection molding material is widely used in the food storage and packaging industry because it doesn't let chemicals mix with food products. Polypropylene (PP) can be washed in hot water without degrading, and it has high chemical and moisture resistance. PP has incredible impact strength, elasticity, and toughness. Designers should also note that PP is easy to recycle, and because of its flexibility, it can be used to make live hinges that can be bent many times without tearing.
A row of four polyethylene trash bins lined up in a municipal park. This is a common application for PE plastic resin. Polyethylene (PE) is a lightweight thermoplastic molding material that has high chemical resistance, elasticity, and electrical insulating properties. It's not especially strong or hard, but it's inexpensive. You'll find it everywhere in consumer plastic parts, milk bottles, medicine and detergent bottles, plastic bags, and trash cans. PE is also the most common injection molding resin for making toys because it's non-toxic and can take a beating without complaint.
AcrylicA collection of colored acrylic tubes help to demonstrate the cosmetic properties of this common type of clear plastic resin. We use acrylic to produce transparent parts such as windows, view screens, and various lighting equipment. It's often used as an alternative to glass due to its high tensile strength and weather and scratch resistant nature. It takes dyes and colorants very well so you can produce many aesthetic effects. On top of its optical and transparent properties, acrylic is odorless and tasteless and doesn't contain Bisphenol A (BPA). BPA is a harmful organic compound, so plastic injection molding resins like acrylic are considered safe for food storage.
Image of kitchen knife with POM handlePolyoxymethylene (POM) is a type of acetal resin used to make mechanical and automotive parts that would usually be made with metal. This engineering thermoplastic material is very strong, tough, and rigid. It's often used to produce gears, fasteners, knife handles, and ball bearings. Although POM has high resistance towards solvents such as alcohols, gasoline, detergents and motor oils, it shouldn't be exposed to hydrochloric acid and nitric acid.
A collection of nylon quick-release buckles. This is meant to show the durability and versatility of nylon resin. Nylon is often used to produce strong mechanical parts like bushings, gears, and bearings. It's very common in automotive applications because not only is it tough but it helps to reduce weight and lower production costs compared to a metal analogue. You should be aware that, although it's a strong plastic, it tends to absorb water. It's not the ideal choice for marine applications. Nylon is also known by its chemical designation PA (Polyamide).
A decorative collection of polycarbonate CD discs. Polycarbonate is another clear injection molding resin that has excellent optical properties and is extremely durable. When molding with this amorphous thermoplastic material, precise dimensional control can be maintained as it has predictable and uniform mold shrinkage. We use polycarbonate when we need something substantially stronger than acrylic. However, be aware that if you're making optically clear plastic parts the mold tool must be highly polished, which in turn implies the use of a higher grade of stainless steel that costs more. Now, you can see that your choice of plastic resin can very much influence the appropriate mold tool material as well.
When it comes to injection molding resins, there are two types of polystyrene that are commonly used: High Impact Polystyrene (HIPS) and General Purpose Polystyrene (GPPS). GPPS is transparent, while HIPS is opaque. Hard cases for toolboxes and bodies of power tools are also made using High Impact Polystyrene. As with so many things there is a tradeoff to be aware of. On the one hand, PS is tough and durable. It can take a lot of abuse in the field. But that also means it's not very environmentally friendly.
Thermoplastic Polyurethane

Red TPU protective phone caseThermoplastic Polyurethane (TPU) is soft and elastic, with great tensile and tear strength. That's why it's often used to make parts that demand a rubber – like elasticity. You should know that TPU is more expensive than other resins but for many applications, like protective wire and cable sheaths, there really is no substitute. Another advantage is that TPU improves the grip for products that need to be held securely in the hand.
Thermoplastic Rubber (TPR)Thermoplastic Rubber (TPR) resin is actually a mixture of plastic and rubber, and it's easy to use in the injection molding process. It has outstanding chemical and weather resistance and high impact strength. Because of this, TPR is used in many types of fluid dispensers, flexible hoses, catheters, and other places containing different liquids, including acid.
You can find this recyclable material in medical catheters, suspension bushings and headphone cables. Thermoplastic rubber is also known as thermoplastic elastomer (TPE).
We hope this brief overview helped you to understand some of the most popular kinds of injection molding resins as well as their properties and applications. Request a quote!

Vacuum casting materials

Vacuum Casting Materials

Below you will find a list of the most common casting resins that we use at Kaierwo.  If you have special requirements that are not addressed here, just let us know and we can special order any commercially available resin.

Vacuum casting polyurethanes resins (Transparent PU, Soft plastic PU, ABS PU, PP/PE PU, Polycarbonate PU)
MaterialSupplier (Country)Material SimulationStrength ShoreFlexion(MPA)TC  MaxProduct color descriptionAdvantage/DisadvantageShrinkage
PU8150Hei-CAST (Japan)ABS83 shD179085Amber,white and blackGood resistance1
UP4280Axson (France)ABS81 shD220093Dark AmberGood resistance1
UP5690Axson (France)PP75-83 shD600--130070White/BlackGood resistance1
PU8400Hei-CAST (Japan)Elastomer20-90shA//Milky white/BlackGood Bend1
T0387Hei-CAST (Japan)Elastomer30-90shA//ClearGood Bend1
PX 527Hei-CAST (Japan)PC85 shD2254105White/BlackHigh T℃ 105°1
PX223HTHei-CAST (Japan)PS/ABS80 shD2300120BlackIdealTG 120°1
PU8263Hei-CAST (Japan)ABS83 shD180085White94V0 flame retarding1
PX330Axson (France)Loaded ABS87 shD3300100Off WhiteV 0 far 251
PX522HTAxson (France)PMMA87 shD2100100ClearColoration TG100°0.996
PX521HTAxson (France)PMMA87 shD2200100ClearColoration TG100°0.996


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We always insist that meeting customers' needs is to realize our value!