Quick Answer: Can You Harden Rebar?

Can you quench in water?

Water is one of the most efficient quenching media where maximum hardness is desired, but there is a small chance that it may cause distortion and tiny cracking.

When hardness can be sacrificed, mineral oils are often used..

Why do blacksmiths put metal in water?

Blacksmiths put metal in water because water submersion will allow the forger to control the brittleness and overall strength of the metal. This is referred to as “quenching,” and is used by many blacksmiths to decrease the risk of breakage when crafting new pieces.

Which quenching medium produces the slowest quench?

Liquid cooling starts when the surface temperature of the metal reaches the boiling point of the liquid so that vapor is no longer formed. This is the slowest stage of cooling.

Should I quench in water or oil?

Water quenching is a rapid cooling, where water as a qenching medium extracts heat much faster. While oil as a medium will extract heat much slower, hence rate of cooling will be slower than water.

What oil do you use to quench?

Mineral Oil Oil is a third traditional quenching agent, suitable for high-speed steels and oil-hardened steels, and in fact for any steel for which the required degree of hardness is achievable. Oil has a slower rate of cooling compared to either water or brine, but faster than air, making it an intermediate quench.

How do you harden steel with motor oil?

One way to do this is to make the steel red-hot, then plunge it into motor oil. The carbon in the motor oil bonds with the top layer of red-hot steel molecules and forms a tough outer covering on the steel. One last step is necessary, however, before your hardened steel is ready to work with.

Why do Bladesmiths quench in oil?

The oil in the quench tank causes the steel to cool rapidly and evenly. If the steel does not cool evenly for some reason, then the blade can warp or even fracture. … Quenching traps cementite within the ferrite and creates a very hard steel called martensite.

Can you temper rebar?

Rebar is made in all different grades, and it’s impossible to heat treat it consistently. If you want a good knife, go to the local scrapyard, and pick up some old coil springs and leaf springs from cars. … Sure, heat treated steel can be sharper and will hold its edge longer, but bronze and iron age knives did exist.

What kind of oil do blacksmiths use to quench?

The two most common food grade oils used in this process are peanut and canola oil. Both of these oils have high flash points which is good for the quenching process. You will need to preheat these oils to slightly higher temperatures when compared to commercial quenching oils (120 – 130 degrees Fahrenheit).

What is the difference between tempering and quenching?

The process of quenching or quench hardening involves heating the material and then rapidly cooling it to set the components into place as quickly as possible. … Tempering is achieved by heating the quenched material to below the critical point for a set period of time, then allowing it to cool in still air.

Is rebar good for knives?

Rebar is junk, its soft, won’t take an edge, and contains alot of impurities, leaf springs work good, so do old files, old double buck saw blades work really well if you can find them. the best is old tool steel if you can come by it.

Can you harden plain steel?

On the downside, mild steels are generally harder to work with when it comes to only heat treatment and quenching. It is possible to do it, but there would be little to no change. Due to its low carbon and alloy elements content, mild steel does not form a martensite structure when quenched after being heated.

Why are steels quenched in oil not water?

Water-quenched steels will generally be harder than oil-quenched steels. This is mainly because the thermal conductivity of water is higher than the thermal conductivity of most oils (that I know); consequently, the rates of cooling will be less rapid (or lower) in oils compared with water.

Can you use vegetable oil to quench steel?

Quenching Oil. Realistically, just about any kind of oil would work for this. Vegetable oil, olive oil, peanut oil, motor oil, used motor oil, etc. It will all work. You do not want to use water, however.

How do you harden steel DIY?

Set your steel directly on the oven rack or on a baking sheet. Let your oven heat the piece of steel. During the tempering process, the steel heats up enough to soften the alloys inside to make it less brittle. If you need to use a blow torch, focus the flame tip on the area you want hardened.

How do you harden metal?

The term hardened steel is often used for a medium or high carbon steel that has been given heat treatment and then quenching followed by tempering. The quenching results in the formation of metastable martensite, the fraction of which is reduced to the desired amount during tempering.