Alloy Die Casting Description:

Aluminum Alloy Die Casting A380 is the most common of the aluminum die casting alloys. It offers the best combination of casting and product properties. It is used for a wide variety of products such as garden equipment, chassis for electronic equipment, engine brackets, housings for automotive alternators, starters and water pumps, home appliances, furniture, office equipment hand tools, and power tools. Alloys 383 and 384 are alternatives to 380 that are specified when very intricate components require improved die filling characteristics and improved resistance to hot cracking. Alloy 360 offers high corrosion resistance and superior strength at elevated temperatures than 380. Other properties are essentially equivalent. Alloy 413 offers the best die fill characteristics making it excellent for pressure tightness applications. it is the choice for products such as hydraulic cylinders and pressure vessels. Its casting characteristics make it useful for very intricate components.

Alloy 390 was developed for automotive engine blocks. Resistance to wear is excellent, but ductility is the lowest of the die casting alloys, with elongation less than 1%. Special surface treatment systems allow engine pistons to run directly on the alloy surface, eliminating the need for ferrous alloy liners. It can also be used for valve bodies and bearing surfaces subject to abrasion and wear.

Alloy 518 is used in escalator components, conveyor components, and marine and aircraft applications It offers good ductility and very good corrosion resistance. It can be polished and anodized for a decorative finish. Zinc Alloy Die Casting Zinc alloys are versatile, cost-effective materials which can be used in a diverse range of die casting applications. As precisely formulated metal alloys, they offer the mechanical properties of medium strength metals. Advantages of Zinc Alloy Die Casting Overall, zinc alloys have significant advantages as casting materials for small components, with excellent physical and mechanical properties, castability and finishing characteristics. Hot chamber die-cast zinc alloys can be cast to tight tolerances, complex detail, net shape, and the alloy¡¯s dimensional stability ensure part-to-part consistency over long production runs. Net shape manufacturing is one of the main advantages of hot chamber die-cast zinc alloys.

The most commonly used zinc alloys are ZAMAK™ 2, ZAMAK™ 3, ZAMAK™ 5, Acuzinc. These alloy families offer higher tensile strengths than most aluminum and magnesium alloys, higher yield strengths, greater impact resistance, higher Brinell hardness, and better ductility. ¡¡è Zinc alloys facilitate higher die casting cycle speeds versus aluminum and other metal alloys, more complex shapes, thinner sections, smoother surface finishes, surface finishes, and higher standards of dimensional accuracy. Compared to plastic, zinc alloys are several times stronger and many times more rigid. Their mechanical properties compare favorably with powdered iron, brass, and screw-machined steel. Zinc has inherent EMI/RFI shielding properties.

CNMCast uses only high-grade zinc alloys certified for purity. Although these materials are completely recyclable, scrap is never re-melted or re-used within our process. Zamak 3 die casting is the standard for the Zamak series of zinc alloys; all other zinc alloys are compared to this. Zamak 3 has the base composition for the Zamak alloys (96% zinc, 4% aluminum). It has excellent castability and long term dimensional stability. More than 70% of all North American zinc die castings are made from Zamak 3. ZAMAK #5 offers high tensile strength, hardness, and creep resistance than zamak# 3, and somewhat lower ductility.

It is preferred whenever these properties are required. Some die casters use only zamak# 5, which is usually an acceptable alternative to zamak# 3. ZAMAK #7 is essentially a high purity form of zamak# 3 with slightly higher ductility and lower hardness. The other mechanical properties are identical to zamak# 3.

The alloy also exhibits higher fluidity than zamak# 3 or3 5, which theoretically allows slightly thinner walls. Zamak# 7 may be specified when high ductility is required. ZA-8 is rapidly growing in popularity for pressure die casting.

ZA-8 can be cast in hot chamber die casting machines for fast cycle rates, It has improved strength, hardness and creeps properties over the ZAMAK alloys with the exception of a No. 2 alloy which is very similar in performance. ZA-8 is readily plated and finished using standard procedures for ZAMAK. When the performance of Zamak No. 3 or No. 5 is in question, ZA-8 is often the die casting choice because of high strength and creep properties and efficient hot chamber castability.

ZA-12 is also a good pressure die casting alloy, using the cold chamber process, which provides a sounder structure than ZA-27, as well as higher die-cast elongation and impact properties. For these reasons, die-cast ZA-12 often competes with ZA-27 for strength application. An excellent bearing alloy, ZA-12 is also platable, although plating adhesion is reduced compared to the ZAMAK alloys. ZA-27 is the high strength performer of the zinc alloys and is die-cast using the cold chamber process.

It is also the lightest alloy and offers excellent bearing and wear resistance properties. ZA-27, however, requires care during melting and casting to assure sound internal structure, particularly for heavy wall sections. It may also need stabilization heat treatment when tight dimensional tolerances are required. ZA-27 is not recommended for plating. However, when brute strength or wear-resistant properties are needed, ZA-27 has demonstrated extraordinary performance.