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The hardening of the aluminum alloy by heat treatment occurs in 4 stages.

1. The process of heating up to a predetermined temperature.
2. Solution taking process.
3. The process of quenching quickly to a low temperature.
4. Aging or precipitation hardening.

• Aluminum permanent mold casting; It is an aluminum casting method that is cast into iron or steel alloy molds.
• The mold consists of two parts, a minimum lower and upper mold.
• Iron and steel alloy materials are not cast in permanent mold casting.
• Aluminum material, on the other hand, does not interact with the mold as it melts at 660°C. This makes aluminum metal the most commonly cast material in permanent die casting molds.
• The rapid freezing of the material in the aluminum permanent mold casting mold allows us to produce a lot in a short time.
• In the aluminum permanent mold casting method, before casting, the mold is heated to a certain temperature, paint is poured into the mold and the mold becomes ready for casting.

• Aluminum with a specific gravity of 2.7 g/cm3; It is one third as heavy as iron (7.9 gr/cm3) and copper (8.9 gr/cm3).
• When aluminum comes into contact with air, a thin oxide film forms on its surface and in this way the metal is protected from corrosion. In addition, with the help of anodization (anodization), corrosion resistance can be made much more effective.
• Easy shaping of aluminum makes the material suitable for production for various forms such as foil, rod, pipe and cable.
• Aluminum is non-toxic and odorless. Its surface is smooth, easily washable and hygienic as it does not contain germs.
• While materials such as steel are brittle at low temperatures, aluminum maintains its strong structure.
• Aluminum can be easily surface treated or painted chemically or electrochemically.
• The electrical conductivity of aluminum is 60% of that of copper.
• The thermal conductivity of aluminum is three times the thermal conductivity of steel.
• Aluminum can be easily recycled. Also low melting
  Due to the temperature of the process, the process takes place economically.
• Aluminum is not magnetic.

In 6XXX series alloys with an iron (Fe) content of 0.20% or less, a glossy surface is obtained when the profile is polished. If the amount of Fe is higher than this value, the color of the profile starts to turn gray and the gloss becomes dull. Fe content should be at least 0.18% to obtain a matt surface. The higher the amount of Fe, the more comfortable and attractive matte surface is obtained. If the amount of Fe is more than 0.30%, it will cause a dull appearance after anodizing, and it also makes the extrusion process difficult.

Various metals are mixed to give aluminum different properties. Classification is made according to the added metals. An alloy is identified by a 4-digit code. The first digit indicates the base metal to which aluminum has been added.

1XXX :  Unalloyed aluminum,
2XXX :  Aluminum alloy with copper,
3XXX :  Manganese aluminum alloy,
4XXX : Aluminium alloy with silicon,
5XXX :  Aluminum alloy with magnesium,
6XXX : Aluminium alloy with silicon and magnesium,
7XXX : Aluminum alloy with zinc,
8XXX :  Aluminum alloy with Iron and Silicon,
9XXX : Newly found alloys.

One of the most important factors in manufacturing efficiency in extrusion presses is dead time. Dead time is defined as the time remaining outside the time when the billet turns into profile during the production of the press. In other words, it can be described as the time that passes during the execution of auxiliary movements.

In the calculation of the dead time, the measurement starts when the previous print is finished, that is, when the pressure drops to zero. The measurement is terminated when the next billet is loaded into the hive, completing the venting process and reaching the maximum pressure. The value read is expressed as the dead time of the press.

Although it does not have a clear definition in the literature, it is the process of converting the raw material to profile per unit time. Generally, it is calculated with 4 different methods. These ;

1. By measuring the punch speed per unit time (mm / sec).
2. By measuring the profile speed (m / min) per unit time.
3. By measuring the amount of net production (kg / h) achieved per unit time.
4. It is calculated by measuring the amount of gross raw material (kg / h) consumed per unit time.

It is the equipment used to obtain the desired cross-sectioned product during the extrusion process. There are two main types of dies. These;

1. Solid dies.
2. Bridge dies.

It is the process of shaping the metal placed in the mold, which is produced depending on the desired shape, by forcing it to flow with high compression force. It can be compared to squeezing toothpaste from a toothpaste tube. Basically, there are 2 different extrusion methods. These;

• Direct Extrusion
• Indirect Extrusion

The main purposes of preheating the dies before the extrusion process are as follows.

• Extension of die life.
• Ensuring flow balance and reducing the amount of scrap.
• Preventing the billet from sticking to the die surfaces.

1. Aluminum billets are heated up to 400 – 500 °C.
2. After the billet reaches the desired temperature, the lubricant is transferred on it as a thin film. It will prevent the die and material from sticking together due to heat.
3. The ticket is transferred to the carrier.
4. Billet logs are pushed.
5. Aluminum billet billets, which are larger than the die, are crushed by the opposite die while in full contact with the load-bearing walls. As the aluminum is pushed through the die, liquid nitrogen flows around the die to cool the process.
6. In some cases, nitrogen gas is used instead of liquid nitrogen.
7. As a result of the pressure, the billet starts to come out by being squeezed out of the cavity of the aluminum die.
8. During the extrusion process, the temperature is instantly measured and recorded. The purpose of knowing the temperature is to be able to maintain maximum pressure velocities.
9. During the drawing of the extrusion, the extrusion outlet is done by a series of fans along the cooling length.
10. The oxidized part on the billet log is discarded.
    When the extrusion reaches the desired length, the extrusion profile is cut with the help of a saw.
11. The metal is transferred on the cooling table.
12. After the aluminum is moved along the table and cooled, the aluminum is subjected to hardening and alignment processes.
13. The extrusion is transferred to a stretched saw blade and cut into certain lengths.

• The cross-sectional shape of the profile to be produced,
• Extrusion rate,
• The type of extrusion die,
• The force required for extrusion (power of the press),
• The desired mechanical properties of the product,
• The desired surface quality of the product.

Benefits;

• It simplifies the extrusion process.

Harms;

• It negatively affects the surface appearance,
• It causes the mold to wear out quickly,
• Causes roughness and lines on the product surface,

• During the extrusion production of the profile, a sample piece is cut with a saw.
• Cut part burrs are cleaned.
• The profile surface is scanned with the scanning device.
• The measurement is compared with the profile technical picture in the device memory.
• Weight control is done on sensitive scales.
• In this way, deviations in the profile and thickness measurements can be made easily.

It is the ratio between the billet area used in the extrusion process and the cross-sectional area of ​​the profile obtained. Start with a phrase;

Extrusion Rate = Billet area / Profile area

When the extrusion rate is low, little mechanical work will be done on the portions of the shape containing the largest metal mass. Its metallurgical structure will approach the casting (coarse grained) state. This structure is mechanically weak. Shapes with less than 10 extrusion rates may not be guaranteed for mechanical properties.

The opposite is the case when the extrusion rate is high. More pressure is required to push the metal through smaller openings in the die and excessive friction occurs. Normally acceptable extrusion rates are limited to 35 for hard alloys and 100 for soft alloys. The normal extrusion rate range is 10 to 35 for hard alloys and 10 to 100 for soft alloys.

These limits should not be considered absolute, as the actual shape of the extrusion can affect the results. The higher the extrusion rate, the more difficult the part will be to extrud as a result of the increased resistance to metal flow. Maximum pressure is required for the extrusion of hard alloys.

It is the heating of the molds before the extrusion process. The respective temperature should be 50-60 degrees below the solubilization value. Some inconveniences caused by low mold temperatures are as follows.

• It causes mold clogging.
• If the die is cold, aluminum does not flow. Continued printing causes the pressure to rise, resulting in the die breaking.
• Profile size deviations occur in filled profiles.
• It creates inefficiency due to the prolongation of production time.
• Surface quality will be low.
• It causes the oil temperature to increase and equipment damage. Therefore, it causes oil leakage.
• It causes a decrease in printing speed, cooling defects, and therefore not achieving the desired hardness in thermal process.

Heat treatment applied to aluminum alloys can be applied in different ways and the applied process is written next to the alloy number with TX symbols. These operations are expressed as follows:
O: Annealed, F: As produced, H: Hardened, T: Heat treated.

• T1: Cooled after hot shaping process and left to naturally age.
• T2: Cooled after hot forming, cold formed and naturally aged.
• T3: Solution taken, cold formed and left to naturally age.
• T4: The solution was taken and naturally left to age.
• T5: Cooled after hot shaping and artificially aged.
• T6: Solution treatment has been done and artificial aging has been done.
• T7: Solution was taken and over-aged.
• T8: Solution treated, cold formed and artificial aging.
• T9: Solution treated, artificially aged and cold formed.
• T10: Cooled after hot forming, cold formed and artificial aging.

It is one of the types of errors that occur during the extrusion process. It is the general definition given to the defects seen as air gaps on the product obtained. The main reasons are as follows.

• Lack of bleeding system or bleeding at wrong pressure.
• Part billet usage.
• The hive temperature is not suitable.
• Billet temperature is not suitable.
• Failure to clean oxide, oil and metal residues accumulated in the hive.
• The amount of search is not ideal length.
• Excessive lubrication of the cutting blade, punch, sleeve at the end of extrusion.
• Hot cutting process does not cut smoothly.
• Die, barrel and punch axes are not in proper position.
• The intermediate cutting blade creates air gaps by emptying the die ports.
• Incorrect dummy block design.
• Hive liner is damaged.
• There is an air gap in the raw material.
• Inappropriate die design.

One of the defects that occur on the surfaces of aluminum profiles after the extrusion process is the surface lines. The main reasons for the related error are as follows.

• Die surface defects caused by Wire Erosion Cutting.
• Cutting tool traces in the die pre-pool.
• Incorrect pass length.
• Improper nitration.
• High billet temperatures.
• Improper printing speed.
• Surface defects inside the hive (core).
• Not using homogeneous raw materials (billet).
• Faulty graphite material used in the exit stand.
• Unsuitable transfer belts.
• Inappropriate intermediate (stock) distance.

After pressing in extrusion dies, abrasions occur on the die surface.
These abrasions cause roughness on the profile surfaces after extrusion. With the help of the compound layer formed after the nitration (Tenifer) process, the surface is more resistant to abrasion, reducing roughness and extending the maintenance intervals of the molds. It is made with 3-5% cyanide and 37% cyanate salts at 570-580 °C.

Benefits;

• Provides good surface quality,
• It provides good mechanical values.

Damages;

• It complicates the extrusion process,
• It causes the press pressure to increase and the hydraulic oil to heat up,
• It causes damage to the mold by being under more pressure.

• Is there a technical drawing? (must include alloy, weight, tolerance, visible surface, etc.)
• Which international standards will it be produced according to?
• What is the order size?
• What is the end-use length?
• What is the estimated annual usage amount?
• What is surface information? (pressing, powder coating, anodizing, machining, hanger trace etc.)
• What is the packing information? (form of packaging, foil etc.)

The purposes of the heating process applied to the dies in the extrusion industry are as follows.

• Reducing the risk of early die damage,
• Reducing the amount of scrap at the beginning of production where there is an unstable metal flow,
• To prevent the billet from sticking.

It is a very special surface coating for aluminum and is made by an electro-chemical process. The electrolyte used is usually an acidic solution. The aluminum to be coated is the anode of the electrolysis process.

• Extrusion die design.
• Extrusion speed and cooling differences.
• Changes in heat treatment conditions (time, temperature, cooling, etc.).
• Aluminum raw material alloy value differences.
• Matting time differences.

Detection quality is measured by paint stain test, conductivity device (anotest), weight loss test. Error types and solutions are mainly as follows;

• Remaining dust on the material surface;
  • The pH of the bath should be adjusted.
• White powder that comes out as it is wiped on the surface of the material;
  • Improper anodizing temperature.
• Improper detection temperature;
  • Putting the lowest and highest temperature alarm value on the poolside or automation system.
• Inappropriate pH amount;
  • According to the ideal range of auxiliary chemical working, ammonia diluted at low pH level and diluted acetic acid at high pH level should be added.
• Insufficient addition of auxiliary chemicals;
  • Automatic dosing can be done according to production m2.
• The bath should be filtered against the particles that may form. Equal distribution of temperature is ensured by recirculation.

• Anodized profiles with micron or surface defects are processed in the dismantling caustic bath.
• The profiles whose surface coating is removed are rinsed.
  The surfaces are cleaned and rinsed in the neutralization bath.
• Suspension attachment points are changed without waiting for hangers.
• If needed, profiles are satinated.
• It is taken to chemical pool processes again.
• The caustic etching times of the profiles that are processed for the second time should be reduced by half.
• Special stripping baths are used for coatings such as cold fixation etc.
• If the chemical process of the profiles to be processed for the second time is prolonged, the products will be corroded and discarded.

• It is a bath used to clean the stains remaining on the surface after basic abrasion.
• It is recommended to use the bath, which is established with an average of 180-200 grams/liter sulfuric acid before anodizing, to extend the life of the anodizing pool.
• There are dissolved aluminum and auxiliary chemicals in the bath. The purpose of the auxiliary chemical is to reduce the corrosive effect of sulfuric acid.
• Important parameters;
  • Sulfuric acid concentration
  • Dissolved aluminum and alloy concentration
  • Auxiliary chemical concentration
  • Processing time
  • The hanger is the draining time.

One of the aluminum surface treatment costs is its chemical costs. When calculating the amount of chemicals used during the month, the formula beginning period + amount taken during the period-end of the period is used. Afterwards, the g / m2 calculation is made by subtracting the m2 of the material treated with that chemical.

Keeping track of your own consumption according to the industry average allows you to manage your chemical costs. Approximately 70% of anodizing chemical costs are caustic, sulfuric acid and tin sulphate.

• The suspension ports are not cleaned well.
• Aluminum suspension rods are not tightened well to the busbar profile.
• No electric current flows due to the dirtyness of the busbar profiles.
• Bar pool contact point (copper surface) impurities.
• Low anodizing pool concentration.
• Wrong m2 calculation.

Caustic (NaOH) generally has two forms: liquid and solid. It is recommended to use in anodizing plants according to the following items.

• Liquid caustic is generally used because of the ease of dissolution in the anodizing bath.
• Liquid caustic is a chemical that can crystallize below 15 °C. During the winter months, caustic freezing problems are encountered in the enterprises. The caustic storage tank can be isolated and heated to 20-30 °C in electric heaters.
• By isolating the transmission lines of the caustic to the baths and wrapping the heating resistors, the freezing of the caustic in the pipes can be prevented.
• It is recommended that the transmission lines be made of stainless material. Plastic lines will become brittle over time.
• The point of adding caustic to the pool should be below the pool edge, close to the pool working level. (Risk of splashing during addition)
• After the caustic addition process, the lines can be cleaned by blowing air into the line in a closed circuit manner.
• In order to prevent the addition of excess caustic; A timer can be placed on the additional pump. (Pump automatically shuts down after adding pump flow rate and need)
• It should not be forgotten that appropriate protective equipment must be used during work.

It is a test performed according to ISO 3210 to evaluate the quality of anodized coating.

• Area of calculated anodized aluminum part; It is treated with phosphoric acid and chromic acid prepared at a certain concentration.
• At the end of the process, the weight loss per unit area is calculated from the weight loss of the aluminum part.
• The test result should be 30 mg/dm2.

The paint gloss level to be measured with the gloss meter;

• Between 30-70 gloss, at an angle of 60 °,
• If it is above 70 gloss, at an angle of 20 °,
• If it is under 30 gloss, at an angle of 85 °,
• It is performed by using gloss measuring devices with a wider measurement range on surfaces above 200 gloss (gloss).

It is a type of paint consisting of dry and solid raw materials. Generally in its content;

• Pigment: It has a colorant and covering function.
• Filling material: Determines the mechanical properties of powder paint by giving volume.
• Resin: It determines the basic properties of paint.
• Hardener: It reacts with the resin and determines the chemical resistance and mechanical properties of the powder paint.
• Additives: It generally determines the surface appearance.

Paint thickness is measured from five points, each 1 cm² on the sample, and 3-5 readings are taken at each point. The average of the readings at each point is written on the test report as the “measurement result”. If any of these measurement results is less than 80% of the desired value, the sample will not pass (negative result).

• Chrome free passivation is a type of coating that is used instead of chrome+6 in powder coating surface treatment.
• This coating, which is made before the drying oven, ensures that the powder paint and the metal adhere to each other.
• It works in the pH range of 2.5 -3.5 on average.
• The processing time is between 20-60 seconds on average.
• The drying temperature after surface treatment is 100 °C at most.
• The coating weight is required to be 3-20 mg/m2.

It is called by this name because it was found by Michael Faraday. It is a definition given to the area covered with conductive metal, where it does not transmit electricity to the outside of the interior. In this way, the electric field is prevented from entering or exiting.

One of the biggest problems of the electrostatic powder coating process is that the coating thickness is below the desired values. Some of the main reasons for this situation are as follows.

• Spray gun voltages are incorrect.
• Since the paint hangers are not clean, they are not conductive.
• The air pressure to the spray guns is insufficient.
• There is deformation in the paint hoses.
• Powder coating grain sizes are large.
• There is no dry air in the system as the air dryer is out of order.
• There is no static current as the grounding is not done correctly.
• Powder paint has a high recycling rate.
• There is not enough paint in the powder paint hopper.
• Air puffing in the powder coating chamber is not enough.
• Cyclone absorption rate is high.

One of the powder coating mistakes is improper curing. The powder coating manufacturer indicates the ideal curing temperature on the product. In unstable processes; baking oven length and conveyor speed are determined; The residence time of the material in the oven is calculated from the formula Distance = Speed x Time. The thermograph device allows us to control the curing temperature and time of the powder paint. The process steps are summarized as follows.

• Thermograph device probes placed on empty hangers are connected to different points of the hanger.
• The thermograph device passed through the oven is connected to the computer program and the graph obtained indicates how many minutes and how many degrees the material has been exposed to.
• If the temperature is not evenly distributed in the oven, it can be seen in the graph.
• Oven thermometer verification can also be partially checked with a thermometer.

• It is done by applying sinking/slump on the test plate.
• The painted surface is gradually subjected to pitting.
• It is the measurement of cracking or separation of the paint on the metal surface.

• The widespread use of aluminum, thanks to its low specific gravity and high strength, can result in a weight reduction of approximately 300 kg in a mid-class car. This ratio corresponds to 30% of the total weight of the vehicle. (Fuel saving)
• 95% of the aluminum used in the automotive industry is collected and recycled. The scrap value of these materials is over 50% of their normal values. (Cost savings)
• Aluminum material is resistant to corrosion from water and road salts, even if it is unpainted or uncoated.
• Galvanizing, coating or painting may not be necessary for aluminum, which is necessary for steel on non-visual parts and incurs additional cost.
• Aluminum is resistant to corrosion and rust like steel in case the paint is scratched or removed.
• Like some plastic materials, it does not become brittle as a result of desert heat, northern cold or UV rays.

• Eliminating extrusion lines.
• Reducing mold cooling marks.
• Reducing weight loss in caustic etching.
• To obtain a more homogeneous surface appearance.

Since polyamide material is moisture-retaining in terms of structure, it absorbs the moisture in its environment. If the amount of humidity in the body is more than 2%, the assembly will be adversely affected. In addition, as the moisture evaporates during paint curing, bubbles occur on the paint layer on the wick. The main reasons for this problem are as follows.

• Relative humidity in the environment
• Ambient temperature
• Waiting time in the environment
• Thickness of the roving (profile)