Can you harden steel with motor oil?

Hardening steel with motor oil is a way of performing what is called the case hardening of steel. Pure steel is actually too soft for many applications. In order to put a hard layer on the steel, carbon must be fused at the molecular level into the top centimeter or so of the steel.

What kind of oil is used for hardening steel?

Mineral oil quenchants are excellent for oil-hardened steels and steels that require a fast quench rate. They tend to be on the expensive side, but they're highly efficient and have greater cooling capacities for steel alloys. In addition, they have a significant environmental impact since they're not biodegradable.

What is the best way to harden steel?

Steels are heated to their appropriate hardening temperature {usually between 800-900°C), held at temperature, then "quenched" (rapidly cooled), often in oil or water. This is followed by tempering (a soak at a lower temperature) which develops the final mechanical properties and relieves stresses.

Does oil quenching harden steel?

Oil quenching is a common method for hardening alloy steel forgings. It is ideal for achieving the required strength and hardness properties on many alloys.

What liquid is used to quench steel?

Water is an effective medium when the goal is to have the steel to reach maximum hardness. However, using water can lead to metal cracking or becoming distorted. If extreme hardness isn't necessary, mineral oil, whale oil, or cottonseed oil may be used in the quenching process instead.

Blackening Steel With Motor Oil - Dean's How-To

Can I quench with motor oil?

1) Motor Oils

Motor oils are a common type of quenching oil used in both blacksmithing and bladesmithing applications. New and used motor oils can be used for quenching and are both widely available. New motor oil is typically cheaper to use than commercial quenching oils.

What did medieval blacksmiths quench their blades in?

The smith then heats the metal so that both the iron and steel are molten and join. The blade is tempered—transformed from soft, workable metal into a hard blade—by holding the blade over a fire and then quenching the blade in a vat of oil or brine.

What is better to quench in oil or 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.

What oil do blacksmiths use to quench?

Blacksmiths also use oils to quench. While commercial quenching oil is the best quality and the most specific oil, motor oil, mineral oil, and even vegetable oil can yield positive results when quenching.

How do you quench steel in oil?

Heat the steel using a torch or a furnace with bellows. Continue until the steel glows red-hot. Work in a well-ventilated area and wear protective clothing, heavy gloves and eye protection. Pick up the red-hot steel with your tongs and immediately immerse it into the motor oil.

Can I harden mild steel?

A36 is a low carbon or mild steel, and as such cannot be hardened. It can be case-hardened, however, which just means using a chemical treatment with heat to add a thin layer of tough material around the soft steel core.

What is in quenching oil?

They are composed of base mineral or petroleum oils, and often contain polar lubricants like fats, vegetable oils, and esters, as well as extreme pressure additives such as chlorine, sulfur, and phosphorus. Straight oils provide the best lubrication and the poorest cooling characteristics among quenching fluids.

What oil can I use to quench a blade?

Canola, Motor Oil, and the Inconel Probe Test

However, some will also use motor oil. I found a study on 1045 steel where they found canola to quench more rapidly than motor oil so I am going to stick with canola as my “cheap” quenching option to test.

Why do blacksmiths quench in oil?

Hot oils are kept at much higher temperatures and are used to ensure that a part's core temperature and surface temperature do not vary too greatly during a quench. This controls distortion and reduces the risk of cracking.

What is commercial quenching oil?

Quench oil serves two primary functions. It facilitates hardening of steel by controlling heat transfer during quenching, and it enhances wetting of steel during quenching to minimize the formation of undesirable thermal and transformational gradients which may lead to increased distortion and cracking.

Can you use vegetable oil to quench steel?

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 hot does oil have to be to quench?

Quenching into oil above 212°F (100°C) has traditionally been referred to as "hot oil" quenching. Oil temperatures in the 195°F - 450°F (90°C - 230°C) range have been used with both ends of the spectrum normally reserved for special applications.

How long does quench oil last?

Oil Recovery

Quenching and martempering oils deteriorate during use, although most premium quenching oils can last more than 10 years when given reasonable use and care.

Which is used as common quenching agent?

Despite reports of decomposition of DBPs caused by some quenching agents, particularly sulphite and thiosulphate, a survey of the literature shows that they are still the most commonly used quenching agents in analysis of DBPs.

Why are swords quenched 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.

What are the disadvantages of quenching steel?

There are several impacts that should be noted about quenching a material. First, the impact on microstructure can wholly depend on the quenching process and how long it was held at certain temperatures. The percentage carbon in the steel can also impact on the time needed to obtain different forms of the steel.

Why are there no titanium swords?

Titanium is not a good material for swords or any blades. Steel is far better. Titanium cannot be heat treated sufficiently to gain a good edge and will not retain edge.

Can you forge rebar?

Cons of Forging with Rebar

A first major con of using rebar for blacksmithing is its unpredictable nature. Most rebar is not made of quality metals and can even contain dangerous fumes when worked. What is this? You can never be sure what the rebar is made of, so final projects can end up brittle.

Were Roman swords iron or steel?

The roman military swords blade was forged from high carbon steel. By this point In roman history the bloomeries (forges) had talented smiths who had a good grasp on smelting iron ore and producing steel weaponry like those we produce in modern forges.