There are many different alloys used in die casting. Zamak is one of the best known one and it is important to understand all about the Zamak alloys if you want to be involved in this field of work. Basically, Zamak alloys are a family of alloys that all have zinc as their basis. When you learn all about the Zamak alloys, you will quickly find out that they are paired with magnesium, aluminum and copper to create the end product. True Zamak alloys, however, are part of the aluminum family and they have a constant composition of 4% aluminum. Zamak is actually a German acronym, meaning Zink, Aluminum, Magnesium and Kupfer (German for copper). The first company to develop Zamak was the New Jersey Zinc Company, who created it in 1929. Zamak has far higher industry standards than white metal or pot metal, common denominators for other zinc alloys.
All About the Zamak Alloys - the Different Types
There are a number of Zamak alloys. The most commonly employed type is Zamak 3. However, Zamak 2, 5 and 7 are also still found in different commercial applications. When you learn all about the Zamak alloys, you will find that they are most often used in die casts. Zamak 3 and 5 are also used in spin casting.
The Problem with Zinc
Before Zamak, zinc die casting had a huge problem, which was zinc pest. This led to impurities in the alloys made with zinc. What Zamak did was to use 99.99% pure zinc, created by New Jersey Zinc. They did this by using a refluxer during the process of smelting. Thanks to this process, the alloy become far more pure and zinc pest was eliminated. Zamak is incredibly useful, because it can be wet painted and electroplated and it is also possible to coat it in chromate conversion.
All About the Zamak Alloys - What about Mazak?
Morris Ashby, in the United Kingdom, licensed the New Jersey Zamak in the 1930s. It was not available in the United Kingdom at that time, so Ashby brokered a deal with New Jersey Zamak to create Mazak. Mazak is the same alloy, but it is created with zinc that has been electrolytically refined and its purity is 99.95%. The name distinguishes it from Zamak, combining the fact that it is not exactly the same alloy with the name Morris Ashby. However, by 1933, the refluxer was patented by the National Smelting and they then started to produce 99.99% zinc in their Avonmouth plant. As a consequence, Mazak no longer really exists, being exactly the same as Zamak.
The application and the production of Zamak hasn't changed much over the past 80 years or so. Zamak is depicted using a series of codes that indicate exactly how it is made. A good example is the code ZL0430. Here, Z stands for zinc, L stands for ingot (this can also be P for pressure die casting). The 04 means the percentage of aluminum in the alloy (04 being 4%) and the 3 is the percentage of copper (in this example, it is 3%).
There are a lot of different kinds of metals and alloys utilized for a lot of different kinds of industries and functions. These metals and alloys are turned into car parts, airplane parts, toys, and even wires among a lot of other things. In order to keep track of the alloys and metals they use, metalworking companies have developed codes for them and this is where you will get to know about Aluminum 380. Aluminum is a widely used metal in a lot of different places and you can even find them in your own house.
What is this A380?
The Aluminum 380 is one of the older types of alloys you can find being produced by the metalworking industry for other industries to use. In the consumer market, you will normally find aluminum 380 being used for tools around the house and for frames and brackets. If you take a good look at your window frames, chances are they are made of the aluminum 380 material. If you have a look at the builders' hardware section you will be able to find tools and enclosures made of this same material. If you are looking for general hardware such as knobs, handles, and press frames then you may just run into some that are made from this 380 alloy.
This alloy can also be used in many an industrial settings because it can be used to make things such as pump fixtures for one. If you are ever in need of some levers, housings, and valve bodies then it is very easy to find the ones made out of aluminum 380. If you are on the lookout for some high strength yet thin walled die castings this is the metal you ought to be looking for.
Specific Properties of the Alloy
This is a very interesting alloy though it may not be one of the more cutting edge ones. When talking about its specific physical properties, it has its specific gravity at a 2.71 rate. Its density is at.0098lb/in3 at 68f. When it comes to the melting point -solidus you will find it at 1000f whole its melting point-liquid is at 1000f as well. Electrical conductivity is 23% IACS at 68f and its thermal conductivity is 55.6 BTU /ft/(hr/ft2/F) at 68F.
Final Thoughts on 380
What you have to know about the 380 is that it is one of the more commonly used aluminum die casting alloys you can find. This explains why you can find it being used in so many places and instances. While the a380 is able to meet the density and mechanical property targets for a lot of different uses its maximum tensile strength is at 47 ksi and its yield strength is at 23 ksi. This alloy's density is at.095 lbs/ in^3 although the thermal conductivity is about 20% lower compared to what it was designed to have. This means the alloy may not make the wisest choice for some uses.
The process of die casting was originally started specifically for the automotive industry. Although we are in a global economic depression, the automotive market is still growing, particularly in foreign countries. In fact, the Ministry of Foreign Trade saw a growth of almost 20% in 2010. Die casting and mold casting is very similar, but die casting is injected under higher psi pressure. As a result, the automotive die casting & auto die cast parts are more uniform, the surface finish is far better and dimensional accuracy is greatly increased. In fact, the accuracy is up to 99.8%. Through the process of die casting, there is often no need to have any further machine involvement after the part has been created. Sometimes, a little bit of machining is needed so that the dimensions can be brought to size. Die casts components have such a great surface finish that no other manufacturing process can achieve the same. Furthermore, the process is such that the finish of the surface is aesthetically pleasing, which also cannot be achieved by other methods of manufacturing. It is possible to make both painted and electroplated finishes, which can look as good if not better than a molded thermoplastic. Die casts are superior to thermoplastics not just because of their aesthetics, but also because the structure of engineering can only be achieved through metals and not through plastics.
How Die Casting Works
During the process of die casting, molten metal is injected into two parts of a shape (the die), which are stuck together. The metal is injected under high pressure. After it has cooled, the two parts of the die come loose and the part is removed. Because the same die is used again and again, each part comes out looking exactly the same. The process of designing the die is the only technically difficult part of the operation. A lot of factors have to be considered to make sure that no air gets trapped inside the molten metal when it is injected and calculations on the draft angle have to be made to make it possible for the part to be ejected easily. This process is used in almost every industry in the world and it is unlikely that you are not surrounded by items right now that have been created through a die casting process.
Automotive Die Casting & Auto Die Cast Parts
The process of die casting is hugely popular in making parts that are used in domestic properties, but also in the architecture of businesses. The most common application, however, is still the automotive industry. Cars have many parts that have been created through die casts. In fact, listing them all would be almost impossible. However, let's take a look at some of the most commonly found automotive parts that have been created through die casting methods.
Engine Parts in Automotive Die Casting & Auto Die Cast Parts
Almost every part of the engine is created through die casting. For instance, the cylinder heads on the engine are made through the process of die casting. Also, all the parts on the gas engine are made almost completely out of die casts. Generally, the alloy that is used in these processes is aluminum.
The Stator in Automotive Die Casting & Auto Die Cast Parts
The stator is generally also made through die casting. Stators have many variations in size. This is why using die casts is such a good method, because it allows for different sized mechanical parts to be created with the highest degree of accuracy every time.
Brackets in Automotive Die Casting & Auto Die Cast Parts
Brackets are also created through the process of die casting. Brackets are used in the electrical part of the motors. Also, stepper motors also use die casted brackets and these are generally created as per the specifications of the customers.
Electronic Covers in Automotive Die Casting & Auto Die Cast Parts
Electronic covers are created in many parts of cars. You will see them on the gearbox for instance, but also the shades pole, the motor and on the stepping motor. These are but a few examples of where electronic covers are used through die casting processes.
Other Automotive Die Casting & Auto Die Cast Parts
There are many other parts within the automotive industry that are made through die casting methods. For instance, the heat sink and the auto fork are made through die casting. In fact, there are very few parts of a car that aren't created through die casting.
If you like cars and are interested in how they are manufactured, you may want to speak to the manufacturer and ask about how it was created. You will be able to look at your vehicle in a completely different light. Why not walk up to your car right now and see if you can identify the parts that have been created through the process of die casting.
If there is one material that is widely used in a lot of different industries, it has to be aluminum. This is one material that has plenty of uses due to the fact that it is light and can suffer intense corrosion, which only leads to one of its greatest strengths. As the corrosion forms on the aluminum it forms a very well formed oxidant layer (Al203) which in turn prevents anymore corrosion from forming. So you can say that the fact that aluminum is easy prey for corrosion eventually makes it one of the best materials to use for protection against corrosion. There are many wonderful things about aluminum and no one can refute that it is indeed useful, but it has to be said that one of its greatest weaknesses is the fact that it lacks strength when in its pure form. This has made it necessary for people to look for other metals they can add to aluminum so they get a stronger end result.
Discovery of Alloys
What they wanted to do was to get around the lack of strength in the aluminum and yet still be able to preserve its low density factor as well as its light weight feature. What they did was look for other elements which were added to the aluminum so they can "pin" down its dislocations which mean they got reduced ductility but they increased the strength of the metal. It is by this method of creating allows for the creation of alloys which can be as strong as steel. There are many different elements that can be added to aluminum and each different element will produce different results but it is a given that the alloys are stronger than the pure aluminum.
If you were to add copper to aluminum this will increase its strengths and the added hardness will also make it heat treatable. Using a classification system that is currently being used, all aluminum alloys have a 4 digit number. The ones that have copper in them have a code that begins with a two and will look like this: 2---. However, copper is not all that you can add to aluminum because if you were to add magnesium to aluminum, you will get a metal that has increased tensile strength and a metal that also has increased resistance to marine corrosion. This end result will also be easier to weld. Alloys that have magnesium begin with a "5" as opposed to the "2" and are used for the ones with copper.
There other common elements added to aluminum that make for varied and very interesting alloys. One of these common elements happens to be Manganese, which also gives the metal increased strength and more resistance to corrosion. If you were to add silicon to aluminum however, you will get an end result that has a lower melting point and yet has improved casting ability. The aluminum alloys that have zinc however get to have increased strength and hardness. What makes aluminum alloys so special is they are able to keep all the lightweight properties of the aluminum and they gain extra properties which aluminum lacks.
Why are Alloys Stronger?
You may be wondering how the addition of such elements to the aluminum makes it stronger, and it really just concerns the structure of aluminum. You see, the structure of aluminum has dislocations that make it extremely ductile and very malleable. These properties are very useful but they are not much use when they do not have any strength which is usually more important. When you use different elements to make alloys they act as plugs to the dislocations and this is what makes the aluminum much harder. Most of the time, the aluminum you see being used in cars and planes or boats are alloys because aluminum in its pure form is simply not strong enough to be used for such things.
Types of Aluminum Alloys
Aluminum alloys can be classified into three types. The first type is comprised of wrought non-heat-treatable alloys which cannot be strengthened by the use of precipitation hardening and they are primarily hardened with cold working techniques. Under this category, you will find the commercial pure aluminum series which has the code 1---. You will also find the manganese-aluminum series (3---) plus the silicon-aluminum series (4---). The magnesium-aluminum series (5---) can also be found under this category. Do take note that some of the 4--- alloys can be toughened by heat treatment while most can only be hardened by through the cold working process.
There are also wrought alloys that are heat-treatable and are able to undergo precipitation hardening which makes the alloys develop maximum strength levels. The alloys that fall under this category are the 2--- series (Al-Cu-Mg and Al-Cu) and the (Al-Mg-Si) alloys or 6--- series alloys. The 7--- series alloys also fall here (Al-Zn-Mg-Cu, Al-Zn-Mg). Aluminum-lithium alloys that belong in the 8--- series also belong in this category. Do take note though that the 7--- and the 2--- alloys which are the ones that tend to develop the highest strength levels are the ones mainly used in metallic aircraft structures because they are the only ones that can withstand the stress and the pressure these structures demand.
Last but not the least are the casting alloys, which include heat treatable and non-heat-treatable alloys. In this category you will find the 2--.- Al-CU series, the 3--.- series Al-Si + CU or Al-Si +Mg. you will also find the 5--.- series Al-Mg and the 7--.- series Al-Zn. Most of the time, you can find the 8--.- Al-Sn alloys in this category as well. The 2--.-, 3--.- and the 8--.- aluminum alloys can be strengthened with the use of the precipitation hardening process, but the properties you will get may not be as good as the ones for wrought alloys which are heat-treatable.
Final Word on Aluminum
Aluminum in its pure form will have very limited uses but it will perform the tasks for which it is applied to exceptionally well. To truly get the most out of this material then alloys will have to be formed. Different alloys are created for many different uses in many different industries.
Die casting is a huge industry. In fact, there are very few items around us in our everyday lives that haven't at least in part been created through die casts. Companies like Dynacast are highly experienced in creating different types of die casts. By visiting http://www.dynacast.com, you will be able to see such die casting design solutions as cold chamber casting or technology that uses thin aluminum walls. Perhaps you are looking for die casting design solutions that are reasonably simple, or perhaps you want hugely complicated and detailed parts with multiple sides. It can all be created by working with the right kind of company.
What Is Involved in Die Casting Design Solutions
One of the great benefits of die casting is that the only complicated part is the creation of the die. This is why you need a company that is able to do this for you. By discussing your requirements, they are able to come up with the best die casting design solutions for your needs. They are involved in the engineering of the die, they work out what strength is needed, they calculate the weight, thermal characteristics and rigidity. The responsibility you have is to indicate what you want to achieve and to find a company that can provide you with this at the best value for money.
Examples of Die Casting Design Solutions
A good example is the fillet radii. Many designers neglect to properly look into this, which demonstrates the importance of working with an experienced and trusted company. Fillet radii are used to make sure that there are no high stress concentrations in the die. Both the external and internal component edges should use fillet radii. The only part where it is not used is the parting line. Through the fillet radii, the die can be filled properly.
Through good die casting, the process of manufacturing should be much quicker and simpler. Companies who use die casting processes generally find they save a great deal of time and money. However, this is only possible if you work with the die casting company from the word go. This means you can fully utilize their superior engineering knowledge. A good company will be able to provide you with free design solutions, so you at least get an idea of what is possible. They can provide you with all the information you need on the appropriate finish on your part (such as vibratory finish, shot blast, thermal deburring and so on). They will also provide you with the best solutions in terms of the surface finish that is most appropriate (such as plating, cleaning, painting or coating) and the best way of machining it (reaming, drilling, tapping and so on). Then, they will provide you with advice on how to join and finish the product and they will help you with your own assembly operations. These are but a few of the things that a die cast design company can mean for you, but it makes it clear why these companies are so important.
Through die casting, it is possible to create pieces that are exactly the same in very high volumes. Simply put, molten metal is injected under high pressure into a die. Because the dies can be used over and over again, the casts are always almost exactly the same. It is possible to choose different types of alloys in die casting, depending on how they are used. The hardest part of die casting is designing the product. Often, the requirements are not just mechanical but the way the finished product looks is also very important. Sometimes, they need very thin walls, bosses or ribs. There are different ways to achieve this, with each method requiring a specific kind of draft angle. The draft angle makes it possible for the piece to be ejected from the die after it has been cast. If the piece hasn't been designed properly, the entire process can go wrong. There are numerous things to consider in the design process, let's take a look at some of them.
Draft Angle
The draft angle, in essence, is the slope that is found on the walls of the die. When you look at the way the die and the sliding cores open, you can identify the angle. This way, a cast can easily come out of the die. The angle is hugely important, since it makes it possible for the cast to slide out rather than stick to the sides, thereby making the process more efficient and the product of higher quality.
Undercut
It is important to keep in mind that high velocity and high pressure is used to cast a die. Once it is then solidified, the two parts of the die open up, ejecting the part. This is why it is so important to make sure no undercut areas are present in the opening direction. So, the draft angel has to be determined before the die or tool is fabricated. Die casting is becoming ever more complex, which means new features are added. These features do have an undercut from time to time, which requires extra cores to be added. This way, the cast is still able to slide out of the die. This demonstrates the importance of calculating the die casting draft angle.
Uniform wall thickness
The wall thickness has to be completely consistent. If the thickness or the geometry changes suddenly, the flow of the molten metal coming into the die will be disrupted. As a result, air can come into the metal and the surface finish will be very poor. Again, ensuring the draft angle is properly calculated will avoid these problems.
Parting Line
Any part that has been made in a die cast will have a parting line. This is where you can see the two halves meet. The parting line or P/L is always indicated on the drawing of the part. Dimensions with critical tolerance should always relate to a specific side of the die. The two sides are the ejector and the cover. Critical tolerance is hard to control on the parting line itself. Also, the parting line should not be the site of a specific feature of the component, since it will not look aesthetically pleasing. Calculating the die casting draft angle will make the line more or less visible.
Fillets
It is very rare for a part that is made through die casting to be flat. Hence, a curved surface is added on the spot where two intersections meet. This stops sharp corners or edges from appearing. Very often, a rounded edge is added to the die casting draft angle so that the molten metal can easily flow into the die. Also, the thermal stress on the part is reduced this way, so the die lasts longer.
Bosses
A die cast part also regularly has a boss added, which is where other parts can be mounted. Generally, the bosses include center holes, so that other machining processes can function. It also makes sure that the thickness of the wall is more uniform. Bosses are very narrow and they are embedded on the die itself. They can make it very difficult for the molten metal to get into this area, which once again makes calculating the draft angle so important.
Openings
One of the most common applications for a die cast part is telecommunication and electronics. These types of products often have displays and keypads and they make it necessary for a die cast part to have an opening that the connectors and keys can hook into. They also need larger openings, for LED or LCD displays for instance. These are highly specific features and they make it more difficult for the molten metal to properly fill the die. So, cross feeders and bridges get added to the component of the die cast. Each of these areas needs to have the right temperature and overflows are also added. Because of this, it becomes easier to manufacture the component and it will make the part of greater quality. So long as the die casting draft angle has also been properly calculated, the features can be trimmed without difficulty. The draft angle will make it possible for the part not to grip too tightly to the die, so that it can be ejected with ease.
Lettering
Very often, lettering is also added to the part. This includes trademarks, identification numbers or logos for instance. Some also want a date added to the part so that it is clear when they were manufactured. It is possible to do this by having raised letters, which is cost effective and therefore generally the option of choice. In this option, the lettering is embedded into the cavity of the die itself. This produces higher quality lettering, since they will be protected from wear and tear. The second option is to use depressed lettering. Here, the feature will protrude on the die, and this makes it of less quality because it will wear and tear quicker. The draft angle must be properly calculated with both these options however, so that the lettering doesn't catch when it is ejected.
There are many ways that you can work metals today but one of the most popular processes still in use has to be die casting. There are two ways to go about die casting. One of them is with the use of cold chamber die casting machines while the other one is with the use of the hot chamber die casting machines. Each machine and process will have its own sets of pros and cons but for now, hot chamber die casting machines and methods are what you will be reading about. This is a very interesting method that produces a lot of great results.
A little Intro on Die Casting in General
Generally speaking, die casting is a type of metal casing which functions with molten metal and gives them shape. Metal that has been heated from solid to liquid is as hot as lava and extreme caution must be taken during the whole die casting process. When engaged in die casting, there are some very important safety regulations that need to be followed so people and machines are kept safe and protected at all times. Die casting is a bit different than other metal casting processes since it needs a huge amount of pressure to be able to force the melted metal into the mold cavity.
Machines for Die Casting
You already know that there are two machines used for die casting. The cold and the hot chamber die casting machines but it is the hot chamber die casting machine that will be discussed here. The first thing you have to know about the hot chamber die casting machine is that it has a number of parts that get it to work the way it does. You will find a burner and a combustion area within the machine which generate heat intense enough to turn solid metal into molten steel. The liquefied metal then sits in a pool in what they call a pot or sometimes a crucible. These hot chamber die casting machines have an intake port which lets the molten metal get transferred into the cylinder which is situated under a plunger. On top of this plunger is the power cylinder which is where the pressure for the process comes from. These machines make use of either hydraulic or pneumatic pistons in their processes are also rated by the amount of force they are able to create. Hot chamber die casting machines use between 700 psi and 5000 psi or force which takes quite a lot of electricity to produce. These machines are also referred to as gooseneck machines, which is in reference to the shape of their nozzles.
Metals Suited for the Hot Chamber Process
You also need to know that only certain metals can be used in hot die-casting machines. One example of a metal suited for the hot chamber process happens to be zinc but other metals that have low melting points and do not attack or erode the metal components of the machines can be casted using this process as well. Some developments in technology and the use of advanced materials also mean this process can be used for some magnesium alloys as well.
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