Aluminio (5)
Artículos relacionados con el aluminio. Suministra las piezas, de conformidad con los deseos del cliente, parcial ó totalmente terminadas y asesora sobre todos los moldes y útiles necesarios.
Ford stole the show at the last Detroit Auto Show with the new generation of its pick-up F-150 has a body made of aluminum alloy. He said that the new model would weigh between 250 and 320 pounds less than the current, largely thanks to the use of aluminum, and it plans to market at prices close to those of the current (which range from 24 500 à 55 000 dollars). The new F-150 is part of the strategy to reduce the fuel consumption of the manufacturer. Ford has not given any indication on vehicle fuel consumption, but according to reports in the press, he would seek a highway fuel consumption of 7.8 liters per 100 kilometers.
Costs most important materials
The decision to replace the steel body of the most sold in the United States and most profitable Ford by an aluminum body vehicle could revolutionize the U.S. utility market, but also reduce the profits of the manufacturer. It implies higher cost of materials, significant investments in production tools and engineering, as well as the risk of setting complicated and troubled production and possible customer resistance. Also the problem of cost of repairing body panels and in turn the amount of insurance premiums.
Easy repair damaged panels
Ford noted in this regard that the model was designed to be repaired easily. It is also committed to financially assist dealers and repair shops for body panels damaged can be replaced or repaired at a competitive cost. Eric Noble, president of the consulting firm The CarLab, estimated that the use of aluminum would increase the cost of the new F-150 at least 1000 dollars, knowing that aluminum is about three times more expensive than steel.Source: www.ccfa.fr
Source: My little blog fonderie
A casting, either cast aluminum or steel, has static mechanical properties (Rm, Rp0.2, elongation) and dynamic (fatigue endurance limit) resulting from a number parameters (part design, alloying elements, ..., fineness of the microstructure).
Important factors
The main factors that impact on the mechanical properties (in both static and dynamic) of a part are:
- The content of alloying elements which enter into the chemical composition of the piece (Al-Si7Cu3Mg for an aluminum or 2.7% C, 0.6 Si, 4.2% Ni and 1.6% for Cr cast Ni-Hard)
- The absence of internal and external defects in the parts of mechanically stressed parts. Generally specifies an acceptable level of default (Class 1 for shrinkage in area designated for example) in the room CdC. The impact of defects on the mechanical properties can be understood finely
- The layout of the room (for example the absence of stress concentration areas or isolated solid areas)
- The type of microstructure obtained. For example, the shape of the graphite (flake, spheroidal, vermicular) or matrix (pearlitic, ferritic, austenitic, bainitic) for the font or shape of silicon (lamellar or acicular) or intermetallic compounds (Al-Fe-Si ) for the aluminum alloys
- The fineness of the microstructure (due to the rate of solidification). For some applications, and specifies the DAS (Dendritic Arm Spacing) in microns for aluminum alloys
- Micro-alloying elements in very small amounts (a few ppm to few% versus the traditional alloying elements)
- A subsequent heat treatment that modifies the microstructure (transformation of austenite to martensite in steels for example). For Al-Si alloys, for example, it is the addition of magnesium during the heat treatment allows to increase the mechanical characteristics
- Machining operations that can result in surface pores or cause residual stresses
- Subsequent treatment (local shot peening or hot isostatic pressing, for example)
Source: My little blog fonderie
Excellent video where you can see step-by-step the filling of a piece of aluminum and plastic at the same time, using a new casting machine.
The foundry institute of RWTH Aachen University presents the new developed hybrid multi-component high pressure die casting process. With this process the possibility is given to manufacture a composite part of two materials (aluminum and plastic) with one tool and one machine.
Silicon is the element of controlling almost all alloy aluminum alloys foundry both gravity sand casting and shell (Al Si7Mg0.3 Al Si12, Al Si7Cu3, ...) in die casting pressure (Al Si9Cu3Fe Al Si17Cu3). Silicon is also used in ferrous alloys where it is added in the form of ferrosilicon. There are essentially three qualities of industrial silicon are distinguished by their level of impurity. The metallurgical silicon has a low level of purity while electronic and solar photovoltaic applications require a purity level much higher. Various forms of silicon
Anodizing of aluminum (or anodic oxidation) is an electrolytic surface treatment can produce a thin protective surface layer and passive microporous alumina (Al2O3) a few tens of microns. The aluminum foundry alloys can all be anodizing treatment.
Principle anodizing SEM anodized layer
What is anodizing?
The functions of anodization are:
- Decoration (many colors)
- The mechanical protection against corrosion, wear (hardness)
- The hanging before painting (not clogged deposit)
- The electrically insulating protective
Handle anodized anodized Lighting
Types of anodizing
There are several types of anodizing:
- Anodizing "hard" in a bath of sulfuric acid (100 microns)
- Chromic Anodizing (a few microns)
- Sulfuric anodizing (10 to 20 microns)
Anodizing decoration (or decorative) can bring a superficial coloration of the aluminum part with pigments (many colors available).
The anodizable alloys
Alloys containing silicon (Al Si family) can be anodization of protection, but are not recommended for decorative anodizing. A high silicon content has a tendency to give a grayish hue. Al MG10 transformed into die casting, provides multiple color decorative anodizing. Al and Al Si2MgTi Mg3Ti (gravity die casting) produce highly decorative colors.
Subset in anodized aluminum pressure
Different thicknesses are achievable anodizing (5 to 50 microns) and depend on the function of the room.
Anodizing operation
The anodizing process consists of a series of bathroom (followed by intermediate rinsing) to prepare a first surface, a second oxide to produce a third color for the potential and the last to stabilize.
Standard
"Specification hard-anodized aluminum and alloys" ISO 10074