How to Select Carbon Steels and Alloy Steels
Carbon steelsare steels in which the main alloying additive is carbon. Alloy steels are steels alloyed with other metals or materials in addition to carbon to improve properties.
Types of Carbon and Alloy Steels
Carbon Steels
Carbon steels are classified based on the amount of carbon content in the steel. The four main classes are mild and low carbon steel, medium carbon steel, high carbon steel, and ultra-high carbon steel.
...
Learn More about Carbon Steels and Alloy Steels
Q & A on Carbon Steels and Alloy Steels
We asked our users for their input on Carbon Steels and Alloy Steels. Here are the results of 429 users familiar with Carbon Steels and Alloy Steels.
Who Took Our Poll? | Design Trends | Applications and Use | Features | Buying AdviceDesign TrendsTop
What new technologies are influencing carbon steels or alloy steels?
81 answers
Corrosion prevention and available coatings and platings (cost drivers), new developments in metals offering new alloys to meet needs, and which also drive new processing to meet product design changes from those materials.
~George F, Manufacturer, Erie, PA
While we focus in areas of wear resistance, we know that there are many new applications for the automotive and energy fields; corrosion resistance and lighter weight, high strength steels are always impressive from a metallurgical point of view.
~John N., Quality Assurance Manager, Welding Engineer, CWI, Warren, MI
Poor quality materials that are permeating all areas of our steel supply. Difficult to find good material anymore; it is always 2-6 phone calls to find steel NOT made in China.
See More Answers
~Burl R., Owner, design engineer, manufacturer and marketing, Chugiak, AK
Applications and UseTop
What are some of the applications you have used carbon steels or alloy steels for?
139 answers
We have used alloy steels for fasteners, fuse pins, and major aircraft structural components. However, we are not designing anything new with alloy steel due to the corrosion issues this alloy family faces in service.
~Dan Wallem, Metallurgical Engineer, Renton, U.S.
Designed/ fabricated machine components. Specified materials for machine components/ tooling/ structural members. Work with selecting and/or developing PM alloys to suit customer applications. Metallography/ failure analysis of wrought and PM steels (plain carbon and alloys).
~Engineering, Process/Production, Cape Town, South Africa
Land based Exploration Drilling Rigs, off shore drilling platforms, Petro/chem plants, power plants; gas fired..coal fired & nuclear, pulp & paper plants, fiberglass plants, dorm bldgs at The Citadel in Charleston, SC and mscl other industries.
See More Answers
~Scott B, Senior Structural/Mechanical Designer, Aiken, SC
Please share with us any “non-standard” applications that carbon steels or alloy steels have been used for.
22 answers
For an assembly press, I used H-13 due to high stresses, thin cross sections, repeated impact loads etc. It worked well, 4140 could have been used for a much lower cost unless heat treating had warped the 4140 enough to require that the part be ground. H-13 is very stable, but very expensive.
~Steve K, Project Manager, Portland, OR
I've seen some structural steel applications being used in the residential area of construction. This has been around for larger houses in the past, however I'm seeing it even in some smaller houses, ie in the 2500 to 4000 sq ft range.
~Scott B, Senior Structural/Mechanical Designer, Aiken, SC
Trailer mounted, offloading rack extenders for expanding unloading range of structural steel pipe delivery trailer. As storage racks for offloading ramps angling towards ground or lower than trailer carriage platform levels.
See More Answers
~Rodney L, Marketing/Sales, Boerne, TX
Do you know of any disastrous mistakes that occurred due to the incorrect usage of carbon steels or alloy steels?
30 answers
1. Stated material properties are based on a coupon test(s) at specified locations within the form roll. These properties may not be consistent throughout the cross section, therefore machining or reshaping steel can leave you with mechanical properties lower than the design intent.
2. Although most carbon steel and many alloy steels are weldable, it pays to check with experts if the application warrants.
~Mike R, Engineer, Edmonton, Canada
We purchased 8620 material and made some pins for a customer. This material was 8620, the certs fell within parameters of 8620, but when the material was heat treated it would not hit the hardness and case depths required. Upon examination, it was discovered that we needed to control the actual range of alloying elements within the steel to enable us to reach the correct end results.
~James D, Marketing/Sales, Kaukauna, WI
Improper baking of hydrogen caused premature failure of a spring beam. Etched-out slag inclusions led to fatigue failure of a fuse pin. Improperly applied corrosion resistant coating did not protect the alloy from oxidation.
See More Answers
~Dan Wallem, Metallurgical Engineer, Renton, U.S.
FeaturesTop
What would your design or feature "wish list" be for this product?
56 answers
Depends upon application - generally a combination of: high strength, high toughness, high ductility, good fatigue life, good machinability, good weldability, potentially formability, creep life, corrosion resistance.
~Research & Development, Rotherham, United Kingdom
Tighter carbon content control for more consistent heat treatment. Many heat treaters have to draw back twice because they have to guess at how the material will react.
~Ralph Russell, Manufacturer, Chicago, IL
When I have need for steel vs. aluminum, plastic, zinc etc. I find that steel works very well. I really don't have a wish list. In the one or two instances where I have preferred a specialty steel, cost drives the design to a more common steel.
See More Answers
~Steve K, Project Manager, Portland, OR
Is there any advice you want to share with users to help them avoid common errors in selection or usage of carbon steels or alloy steels?
49 answers
Don't get blinded by the science - use common sense first and back it up with the specifications later. Ask oneself, what properties are needed for the application, higher alloy steels often make complications later. Only use them when absolutely necessary. The cheapest steel that is adequate is often the best for the job.
~Fred B, Engineer, Burgess Hill, UK
Use carbon and alloy steels sensibly, exploiting characteristics of special steels can often lead to excessive and necessary cost of end products, particularly when lesser steels are more than capable of producing an equivalent product with only the slightest of compromises.
~Alan J, Engineering Consultant, Birmingham, United Kingdom
Machined and fabricated components should be of a stronger material than the keys that hold them together. You want some sacrificial piece or there can be catastrophic damage. For material that will be used in cold environs, check the Charpy's.
See More Answers
~Paul V, Quality Control, Everett, WA
Buying AdviceTop
Do you have any advice for people relative to buying or using carbon steels or alloy steels?
52 answers
Make sure that the material that is being purchased will perform to the engineering specs and will be able to be machined and / or welded to the prints, as necessary, before making the purchase. Also, check for any necessary heat treating actions that may be detrimental to the final condition of the material. Check to find out if material certifications are required before ordering, acquiring them after the fact costs more and is harder to get.
~Paul V, Quality Control, Everett, WA
Ensure that the material is vacuum-melted to reduce the amount of slag inclusions in the alloy. These inclusions are terrible in a fatigue loading environment. Chemical processing of the alloy can also etch out ditches where the slag inclusions used to be to create stress raisers. Hydrogen can also be picked up during chemical processing as well, leading to embrittlement.
~Dan Wallem, Metallurgical Engineer, Renton, U.S.
Pay attention to what engineering specs out on prints and make sure the material purchased meets those criteria. In today's steel market, the alloying elements range so drastically that steel from one supplier might act totally differently than that from another. Especially in the heat treating operations.
See More Answers
~James D, Marketing/Sales, Kaukauna, WI
