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Can Diamonds Cut Through Steel?

Can Diamonds Cut Through Steel?

We all know how tough diamonds are; it’s pretty much engraved in their reputation. Diamonds are made up of a solid crystalline matrix of carbon atoms – although other elements sometimes find their way in the mix. 

The fewer atoms of other elements in the carbon matrix, the purer a diamond becomes. But that tough-as-nails reputation got us wondering; there must be a material that can stand up to these beautiful gems. 

How about a strong metal like steel? Can diamonds cut through steel? It’s a fair question, a kind of a battle of the titans. Diamonds are tough, but are they stronger than steel?

Well, we did some research and found the answers, and they’re pretty interesting. So, be sure to keep scrolling! 

Can Diamonds Cut Through Steel?

The straight answer is yes; diamonds can cut through steel. 

But as with most diamond-related questions, there’s more to it than just the short answer.

Diamond blades, for instance, are used for cutting various materials such as concrete, masonry, steel, and other metals. Diamond particles are on the exterior surface of the blade, which makes it easier to cut. 

There are diamond blades specifically designed to cut steel. They endure longer than abrasive blades – but do not cut as quickly.

As a result, an abrasive blade is our particular favorite. Because the cost of an abrasive cutting blade is so low, the labor savings (time-wise, that is) far outweigh the cost of additional blades.

So what about pure strength? Is diamond stronger than steel? 

When it comes to diamonds, there are three factors to consider. That would be stability, toughness, and hardness. 

The hardest natural material on the planet is diamond – which pretty much answers the last part right away.

Stability refers to how well it resists chemicals, which isn’t what we’re searching for here. Finally, there’s toughness. Toughness refers to how well it can withstand breaking. 

Let’s have a look at the differences in strength between diamond and steel:

The gem’s tensile strength is lower than steel. This measurement refers to how much it can be stressed or pushed before breaking. Diamond is more brittle than steel, as evidenced by this. 

Brittleness, on the other hand, is defined as the amount of energy required to shatter anything.

You should also account for deformation. 

Diamond is a crystal; therefore, when it breaks, it breaks. But steel can distort before it cracks. 

A lack of stretching or deformation also indicates brittleness. Because they expand less, brittle materials are easier to shatter.

You should also consider how a diamond has four cleavage directions. At the molecular level, cleavage is a plane of weakness.

If a diamond is hit on one of these four planes, it will readily break. That’s kind of why cleaving is a diamond-cutting step, by the way. 

Brittle materials have substantially reduced strength due to minute surface fissures. That is due to the fact that when strain is applied, the tension is concentrated. 

When sufficient force is applied to the crack, it expands. The tension might be heightened even further. That’s because the crack is longer. In other words, you get a runaway effect, which looks to break instantaneously.

Steel is tougher than diamond, but diamonds are smoother than steel because the molecules are packed considerably closer together. 

And that also makes them much easier to polish, too. 

Consider how a diamond-tipped drill bit prevents wear and tear by the material it’s cutting gliding around the diamond tip’s smoothness. That smoothness is more or less a diamond technique to make it appear more powerful.

Steel is currently the most robust metal available. Steel has a far higher density than diamond, with each steel molecule weighing much more than a single carbon atom.

It’s made in open-air foundries, where contaminants such as air molecules and other debris can smelt into the steel. And to keep oxygen out of the weld pool, welders employ a shielding gas or flux. 

And because of the strength of the steel in the final product, that’s generally not a concern when it’s manufactured.

So, as a result, no –  diamond is not stronger than steel. But it can still cut through it easily.

Related Read: Why Is Diamond Not Used for the Machining of Ferrous Material?

What Is Used To Cut Diamonds?

Since diamonds are among the hardest substances on the planet, they can be used to cut another diamond automatically. Lasers are yet another possibility – but their applications are primarily limited to bruting and cleaving. 

Typically, the instruments have diamond-bladed edges or discs that are lined in diamond dust. Preparation, cleaving, routing, polishing, and examining are the five stages involved in cutting and polishing diamonds.

Learn More: Can A Diamond Destroy A Diamond?

Phase 1: Rough Diamond Planning

One of the most crucial things to get right when cutting a rough stone is planning. While this might be a time-consuming process, it is also the stage that defines the worth of the finished products.

The cutter will determine the best feasible diamond shapes throughout the design stages to reduce waste and optimize the return on the coarse stone. 

The rock is usually mapped to create precise dimensions. After this data is gathered, computer software is used to create 3D models that show the cutter the best approach to optimizing the rough stone.

Phase 2: Rough Diamond Cleaving/Sawing

The component of the cleaving procedure that involves dividing the rough into distinct pieces is called cleaving. It will allow the cutter to work on the parts separately – while also allowing the rough stone to be fully utilized.

At this point, mechanical sawing is also an option. 

In the case of irregularly shaped rough gems, contactless cutting equipment such as lasers can be used to complete the sawing operation.

Phase 3: “Rounding” The Roughs With Mechanical Bruting

After the diamond is cut, brushing is used to shape the rough pieces that were separated into round stones. Girdling is the term used for this operation. 

Both diamonds are placed on an axle across from each other in this situation. They will turn in opposite directions and grind against one another to create a girdle finish.

Phase 4: Diamond Facet Polishing

The diamond’s facets will be created and formed in the next phase when the rough gem gets molded into a shape. 

The rough stone is polished by the cutter, who also uses a wheel. The diamond’s facets become more reflective and expressive as a result of this process.

This polishing technique is interestingly divided into two steps – blocking and “brillianteering.”

To make one cut rock, eight pavilion mains, eight crowns, one culet, and one table facet are inserted during the blocking phase. This measure’s purpose is to serve as a blueprint for the next step.

The “brillianteer” will then complete the task by adding the remaining facets, bringing the final number of facets to 57. It carries a tremendous deal of responsibility because a gem’s fire and brilliance are determined at this time.

Phase 5 (Quality Control): Inspection Of The Polished Diamond 

The review method is the final stage. That is where the diamond is examined to ensure that it fits the requirements. 

If the rock does not match the quality control criteria, it will be returned to the polishers for a few touches.

Related Read: An In-Depth Guide on Diamond Cutting: How Are Diamonds Cut?

Can Steel Be Used To Smash A Diamond?

Did you know that it is possible to crush a diamond even though it is such a hard material – but it is impossible to smash a piece of steel? 

That got us wondering; will we be able to break a piece of steel with a diamond hammer?

Diamonds are mostly carbon, meaning carbon valence electrons require double covalent bonds on their four outer electrons based on the molecular structure. That means the bond is doubled – and the electrons are held tighter than in other materials with single-bonded electrons.

Diamonds, on the other hand, contain impurities. The material grows underground at extreme heat and pressure levels, and you can imagine that those levels go up and down through time. 

Add to that the fact that diamonds form over a long period, and you will get hard but uneven material.

So, what does all that mean? Well, it means that diamonds are brittle; they can shatter easily.

Steel, on the other hand, is mostly formed of iron and carbon but can be mixed with a variety of other metals in the melting process to improve its heat resistance and strength. 

It also goes through a refining process which lowers impurities in the molten steel and boosts its strength significantly.

The metal can be shaped into a hammer – or any other shape we want. However, diamonds are naturally formed in some pretty strange shapes.

Finally, depending on the steel composite and smelting process utilized, the thickness of the steel sheet, and whether or not it’s reaching a cleaving plane of the stone, the diamond would fracture, break, or tear through steel. 

Heck, let’s throw a different material in the fight. 

Is it possible for diamonds to cut through the toughest glass, for instance? 

Well, there’s a lot of strong glass around. We’ve been perfecting glassmaking for centuries. But glass has a Mohs hardness of only about 5.5. 

At 10 Mohs, diamonds are roughly twice as hard.

To put this in context, a steel file has a Mohs rating of 6.5, whereas quartz has a Mohs rating of 7. Cubic zirconia (“fake diamond”) has a Mohs hardness of roughly 8. 

Related Read: Diamond Vs. Quartz: ​Comparison Guide

On the other hand, glass cannot survive the cutting or scratching force of diamond – even at its best.

Many people mistake bullet-resistant panels for glass, despite being made of polymer and only have a thin layer of glass on top to protect them from scratches. 

As previously stated, glass is normally rated at around 5.5 Mohs, while plastic is rated much lower. As a result, the diamond will have no trouble cutting both the glass layer and the bullet-resistant panel once more. 

But how can diamonds be shaped and cut when they are so hard? How do people cut the diamond into a perfect shape? 

As we mentioned earlier, it pretty much takes a diamond to cut a diamond. It all has to do with anisotropy. 

So, what the heck is that? Well, we’ll explain it all, don’t worry. 

Anisotropy means that a diamond, as a material, is directionally dependent. That is why there is a distinction to be made between ripping and crosscutting. 

Even if diamonds are as tough as the reputation that follows them, you can still create plenty of planned damage if you know the angle from which you need to strike. 

Even though diamonds are mechanically anisotropic, they crystallize in the cubic system and are nearly isotropic in most other respects. Other substances, such as calcite, are substantially optically anisotropic and exhibit pronounced birefringence (double refraction).

An in-depth discussion of anisotropy would require sophisticated mathematics, such as tensor analysis, so we don’t need to go in too deep into the science of it all. 

Here’s a quick and easy way to understand this: Diamonds may look as if they’re a single, whole, dense, and strong object, but they’re not. They are, in a sense, made of small diamond plains. 

On the surface of these plains are the top and bottom layers of carbon atoms that are bonding with the atoms on the next plain. These bonds are strong, sure, but they’re not nearly as strong as those within the material. 

Because of this, if you strike a diamond in the right spot and at the right angle, these bonds will break – and you’ll be able to chip away at and cut a diamond any which way you please.

Read More: Is Steel Harder Than A Diamond?

Final Words

We hope that we’ve given you all the info that you were looking for today. And in conclusion: 

Diamonds are the hardest substance, and they can cut anything – which also includes steel. They’re so strong that there’s only one thing that can cut them – and it’s a diamond itself. These gems genuinely are one of the most fascinating materials on our planet!

Read Also: Why Is Diamond So Hard?