How Zinc - Zinc DieCasting Engineering Database - DEMO VERSION
This comprehensive and up to date Engineering Database for the hot chamber zinc die casting alloys is designed to help Specifiers and Designers to realize their project in the most efficient way by combining the precision and the cost-effectiveness of the die casting process with the exceptional mechanical and physical properties of zinc alloys.
This DB is set up, catalogued and organized in such a way that it allows the use of a dedicated search engine to retrieve the existing pertinent information gathered not only from the available open literature but also from private communication of die casting specialists.
All pictures drawings, etc.. are available as 3D format. Each one can be animated, by a free downloadable specific viewer software.
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DESIGNING ZINC DIECAST COMPONENTS
It is essential for Engineers designing and developing products for a competitive marketplace to specify the most effective materials for the job. They need to know the general attributes of a wide range of materials such that they can rapidly zero in on those most suitable. But materials cannot be considered on their mechanical properties alone; it is the combination of the material and it's possible forming options that must be appraised.
When looked at in this light zinc diecasting alloys have much to offer. They are strong rigid and tough, they have high electrical and thermal conductivity, they can frequently be cast “net shape” and when post casting forming operations are necessary they offer good machinability and ductility. The hot chamber diecasting process used for the vast majority of zinc alloy diecastings provides high productivity and the die life for zinc alloys is outstanding; hence production costs are low.
Zinc alloy diecastings can be finished in a wide range of ways from simple passivation to organic coatings or electroplating, but perhaps the majority are used without any applied finish, taking advantage of the materials good resistance to corrosion in natural environments.
Zinc alloys are environmentally sound, the casting process generates insignificant quantities of effluent, the castings are safe to use and at the end of the products life the zinc alloy is readily recyclable via currently existing technology.
Zinc alloy parts, many pressure diecast "net shape", are used in a wide range of industries. The outstanding consistency of the material and the process are utilised to bring economy, reliability and effectiveness to the assembled products.
The purpose of this publication is to give a good grounding in the attributes of zinc diecasting alloys and the design and development of diecast zinc alloy components. It will help engineers decide whether a zinc alloy diecasting is appropriate, both technically and economically for any particular application and serve as a guide towards a component design that will maximise value and reliability and minimise overall costs. Only the “hot chamber” diecasting alloys are considered here.
Chemical composition limits of hot chamber diecastings made to European standard plus reasons for the imposition of those limits.
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Short Designation
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ZP3 |
ZP5 |
ZP2 |
ZP8 |
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Alloy Number
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ZP0400 |
ZP0410 |
ZP0430 |
ZP0810 |
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Alloy Symbol
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ZnAl4 |
ZnAl4Cu1 |
ZnAl4Cu3 |
ZnAl8Cu1 |
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Aluminium %
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Max. |
4.3
3.7 |
4.3
3.7 |
4.3
3.7 |
8.8
8.0 |
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Min. |
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Copper %
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Max. |
0.1
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1.2
0.7 |
3.3
2.7 |
1.3
0.8 |
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Min. |
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Magnesium %
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Max. |
0.05
0.025 |
0.05
0.025 |
0.05
0.025 |
0.03
0.015 |
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Min. |
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Lead %
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Max. |
0.005 |
0.005 |
0.005 |
0.006 |
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Cadmium %
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Max. |
0.005 |
0.005 |
0.005 |
0.006 |
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Tin %
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Max. |
0.002 |
0.002 |
0.002 |
0.003 |
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Iron %
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Max. |
0.05 |
0.05 |
0.05 |
0.06 |
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Nickel %
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Max. |
0.02 |
0.02 |
0.02 |
0.02 |
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Silicon %
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Max. |
0.03 |
0.03 |
0.03 |
0.045 |
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Zinc
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Remainder |
Remainder |
Remainder |
Remainder |
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Very similar standards used outside of the European Union that may also be specified with confidence.
Helpful when updating designs created prior to that date.
Tensile strength, elongation at break and at Fmax, modulus, yield, hardness, impact strength, fatigue strength.
Provides data required for some engineering analyses.
UTS, elongation, impact strength, hardness.
Yield, UTS, and elongation for wall thicknesses between 0.75mm and 3mm, typical of modern zinc diecastings.
Effect of ageing at up to 150°C on tensile, hardness and impact properties.
Equations relating stress, temperature, time and strain.
SG, thermal expansion, thermal and electrical conductivity, melting temperature.
A link to a program for the design of simple heat sinks.
Post casting dimensional changes and how they are affected by quenching immediately after casting.
Composition limits required for use in potentially explosive atmospheres.
Includes a link to the extensive monograph “Zinc its Corrosion Resistance”
also including the combined effect of corrosion and ageing on mechanical properties.
Considerations when using zinc diecastings in contact with a variety of natural waters.
Corrosion rates to be expected in salt water
Acceptable pH range and a link to “Zinc: Its Corrosion Resistance” which details effects of a wide variety of common chemicals.
Gives details of the few organic materials that give rise to problems.
Additional corrosion of zinc alloys resulting from contact with other metals in atmospheric and immersed situations.
A useful reference vs other pure metals and common alloys.
The effects positive and negative of the constituent elements of zinc diecasting alloys.
A very brief assessment of the energy needed to manufacture zinc diecastings.
A brief statement of the environmental status of the zinc alloy and zinc diecasting production processes.
The already existing and well used recycling routes for zinc alloy diecastings.
An assessment of how zinc alloy diecastings compare in general terms with other groups of materials and manufacturing processes. Also numerous mechanical and physical property comparison charts.
Considerations when specifying a zinc alloy for a particular application. Plus a link to a useful selection application which works by prioritising attributes needed for the job.
The criticality of component design to function and production. Team approach to design. Normal casting size range and minimum wall sections. Allowing for adequate gate area. Considering the ease of ejection from the die from the outset.
Considering available die parting lines. Points to be born in mind. Examples of good and bad parting lines.
Wall section range. Examples of the use of the inscribed sphere technique to check section ratios.
Normal and absolute minimum requirements and where they can be used.
Points to bear in mind. Examples of good and bad practice.
Examples of best practice when designing strengthening ribs and rib intersections
Avoiding flat surfaces by crowning or texturing.
Fillet radii, recommended minimums and common practice. Design of transitions at unequal section junctions and angled intersections
Raised or sunk lettering? Height, width, and draft limits
Examples of good and bad practice for cast-in inserts.
How to avoid hot spots by good component design. Examples of good and bad practice.
Examples of how the need for die moving elements can be avoided.
Examples of good and bad practice
External threads. Internal threads
Where to allow for ejector pins to act on the casting, and how much space is needed
Considerations when including cast in bosses
Some techniques for designing cored holes
The influence of proposed service conditions when deciding on the maximum design stress for a component.
Factors to take into account when aiming for net shape casting of precision components.
Factors that affect casting appearance, and some design requirements for subsequent finishing operations.
The consequences (positive and negative) of casting designs that necessitate complex parting lines and/or extra moving parts.
Parts consolidation. FMEA.
Agreeing quality requirements. Relevance of ISO9001:2000 to product quality. Statistical quality and process control
A thorough coverage of the subject as it pertains to zinc diecasting alloys, to enable rapid processing to the required dimensions and surface finish.
A guide towards the most appropriate process and material when a finishing operation is desired either for aesthetic or functional reasons. Advice on casting design features appropriate for each finish.
Taken together this section and that on testing offer guidance towards production methods and materials that are cost effective and yield part performance similar to a diecasting.
Issues surrounding the testing of prototypes or pre-production samples.
A novel test procedure for predicting long-term corrosion performance is outlined.
The factors that affect both initial investment and unit costs are given a thorough airing.
Provides an alternative way of tracking down information.
Those few technical terms used that might not be familiar to a trained engineer are defined here.