Types of Metals
Why aluminum?
Pure aluminum is soft and ductile and most commercial uses require greater strength than pure aluminum affords. So, strength is achieved by the addition of other elements to produce alloys. Further strengthening is possible by means which classify the alloys into roughly two categories, non-heat-treatable (alloyed with manganese, silicon, iron, and magnesium) and heat-treatable (alloyed with copper, magnesium, zinc, and silicon).
Aluminum is available in a wide variety of alloys to meet specific applications. Here we focus on two types of aluminum alloys that are uses mostly for laser cutting applications:
- 5052 - main alloy is magnesium. It is strong and yet forms well with reasonable inside bend radius. Corrosion resistance and weldability is very good. Better salt water corrosion resistance than 1100. Used for outdoors signs, monument signs, backlit signs and any number of parts requiring considerable strength and formability at reasonable cost. Anodizing may be slightly yellowish. Aluminum 5052 is supposed to have better corrosion resistance, more strenght and it machines pretty good plus it's cheaper cheaper than 6061. Aluminum 5052 is also strong and light weight and it can be easily formed into various items.
- 6061 - alloyed with magnesium and silicon. Heat treatable to improve strength. A widely used structural alloy for light to medium strength applications. Requires much larger inside bend radius than 5052, but can be formed. Combines good weldability, corrosion resistance, and strength after heat treatment. Multipurpose Aluminum 6061 is most widely used aluminum alloy due to combination of strength, good corrosion resistance, and machinability. It has a satisfactory post-machining finish and will produce continuous chips.
In general, aluminum is lightweight and offers moderate strength, as well as good corrosion resistance, formability, and machinability, especially when compared to steel.
Aluminum typically melts at a lower temperature than steel; its capacity for conducting heat and electricity is about two-thirds that of copper.
Why Steel?
Steel sheet is commonly categorized as either "hot rolled" or "cold rolled" and by varying the amount of carbon, the manufacturer can produce a wide range of material characteristics. Tool steels have a much higher carbon content than the mild steels used in sheet metal work.
The hot rolling process is generally less expensive, but results in a surface slag that is not always acceptable. Pickled and Oiled Hot Roll Steel has had most of the mill oxide removed and has a better surface appearance.
Cold-rolled steel is commonly used in precision sheet metal applications due to its excellent surface condition, material consistency, and accuracy in thickness.
One main advantage of steel over aluminum is the ease of resistance spot welding.
Steel also has a lower cost per pound than aluminum, although adding corrosion protection (plating and painting) may consume a great deal of the cost savings over aluminum.
Steel sheet is available in a wide range of pre-finished products, including galvanized, paint primered, and fully painted. Laser Alliance LLC, however, mostly laser-cuts bare steel sheets and plates.
Why Stainless Steel?
Stainless steel does rust over time, but in a minuscule amount compared to steel sheet. This is accomplished by alloying elements like nickel to reduce the amount of iron exposed on the surface. There are over 150 grades of stainless steel, of which fifteen are most common. The AISI (American Iron and Steel Institute) defines the following grades among others:
- 200 Series - austenitic iron-chromium-nickel-manganese alloys
- 300 Series - austenitic iron-chromium-nickel alloys. Type 301, highly ductile, for formed products. Also hardens rapidly during mechanical working.
- Type 303 - free machining version of 304 via addition of sulfur
- Type 304 - the most common; the classic 18/8 stainless steel
- Type 316 - Alloy addition of molybdenum to prevent specific forms of corrosion
- 400 Series - ferritic and martensitic alloys.
Although there is a variety of stainless steel alloys. We focus on one alloy that is commonly used in laser cutting applications.
Type 304 is the most widely used of the stainless steel because it has:
- excellent heat resistance
- good corrosion resistance to many chemical corrodents as well as industrial atmospheres
- good formability and weldability by all common methods.
Talk to us today and let's turn your ideas into reality!
Quick quote? Questions? Comments?
Phone: 408-262-3222
Email us:
Form: Quote Request
