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Why Nickel Is Critical In Wear Resistant Steel

There are 3 specific items essential for creating a wear resistant steel the same hardness all the way through the thickness of the steel.

Eliminate any one and your performance suffers greatly.

These items are:
1. Chemistry – having the correct percentages of the proper alloying elements. Without the right elements, your product suffers poor performance.
2. Heat Treat Process – most wear resistant steels have been heat treated to increase hardness and ductility. If the description doesn’t mention heat treated, it will only be surface hardened.
3. Removing Sulfur and Phosphorus – down to .001%. If you do not, your steel will be very crack sensitive.

Nickel is a critical element in making through hardened wear resistant steel.

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Nickel is used as an alloy primarily along with other elements such as Chromium to make stainless steels and alloy steels. Nickel and Chrome are excellent partners for creating alloy steels with hardness and strength. It all depends on the ratio or each.

Adding Nickel alloy to steel has several beneficial properties:

• Improves through hardening properties.
• Increases strength.
• Increases toughness.
• Reduces effects of shock
• Reduces effects of corrosion.

Why Is This Important?
Through hardness means your wear resistant steel has the same hardness throughout the thickness of the steel.

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Without enough Nickel, a wear plate will only become hard on the top and bottom surfaces. The center will not be much harder than mild steel. If you have had wear plate rapidly wear away after it appeared to work well; that is what happened. You finally wore though the thin hardened top layer. Much like the softer center in an Oreo® cookie.

The majority of wear resistant steels on the market claim to be through hardened, but they do not have enough Nickel content to allow the heat treatment to fully change the metallurgical structure.

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Steel is first made into a large cast rectangular bar called a bloom. It is then rolled over and over to create the correct thickness, width and length. After rolling the plate to the proper size, it goes to be heat treated. Photo from Medium.com.

For heat treating wear resistant steel, the plate is first heated to 1,650°F to eliminate the current metallurgical structure.


THIS IS THE HEAT TREATING OR QUENCH AND TEMPER PROCESS

Quenching

Taking the orange hot plate from the oven, it is ‘Quenched’ by lowering it into a water tank the size of a swimming pool. Going from 1,650°F to being dunked in water, this shock changes the molecular structure of the steel. This hardens the steel.
If you take mild steel, heat it red hot and dun it into water; it will largely be the same as it was previously. This is because mild steel doesn’t contain any alloying elements.
Quenched steel is very hard, but is too brittle to use in the quenched only condition. At this point it is difficult to weld and forming is not practical. It would not withstand significant impact without cracking. So the steel has to be tempered.

Tempering

After the steel has been removed from the quench tank, it cools to ambient temperature. Then it is re-heated to a very specific temperature; usually between 400° and 500° F, and held there for a specific length of time.
This results in wear plate that has slightly reduced hardness, but has the ability to withstand substantial impact in use. This is what truly makes an industry leading through hardened wear plate.


THE IMPORTANCE OF NICKEL IN HEAT TREATING

Obviously when the orange hot steel is dunked into the pool for quenching, the surface is instantly transformed to the desired metallurgical structure. The heavier the steel plate, the more gradual the transition to the desired metallurgical structure inside the thickness of the plate.


More Nickel in the wear plate chemistry allows the metallurgical structure change to take place at a slower pace. If there is not enough Nickel present, this transition cannot occur.

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The ASTM A 255 Hardenability Profile test is called the Jominy Test. CLICK HERE for a brief 2-minute video that clearly illustrates this point.

Watch for the following important details in this video.

There are no vocals telling you what to specifically watch for:

• At 0:23 it shows machining a test sample into a round bar. Every material tested is made to this same size.
• At 0:30 the round bar is placed into an oven set to 1,550°F to remove any prior metallurgical structure. This is the heat treating. A probe is place at the top end of the round bar to assure it achieves the correct temperature.
• At 0:55 the round bar is removed from the oven and placed into the test stand. NOTICE the bar is placed so only the very bottom is in contact with the water bubbling up. This is how hardening occurs due to quenching.
• At 1:10 you can see the cooling effect as it transitions up the bar as the steel cools. Having the correct amount of Nickel in the steel allows the proper metallurgical structure to form. This is how you achieve through hardened steel.
• At 1:20 the steel round bar has a flat ground onto the round bar. This allows accurate hardness testing to occur.
• At 1:40 it shows the Rockwell hardness testing machine which takes 30 different hardness readings on the bar, every 1/16”. This shows you what a difference Nickel makes in the ability to have wear resistant steel actually be hardened through the steel. The hardness of most AR test samples drop off rapidly. This is why you have likely never heard of the Jominy Test previously.


Here Is The Bottom Line:

Nearly all AR400, AR450 and AR500 do not contain enough Nickel to achieve the same hardness throughout the thickness of the plate.

This is why when some steel companies claim their steel has 0.15% Nickel in their wear plate, we immediately know they do not have enough Nickel alloy to achieve through hardness.


Most companies cannot get the same surface hardness at the center of a 1” thick plate.

By comparison, JADCO QT Plus ® guarantees 100% hardness at the center of a 3” thick plate.

This is because JADCO QT Plus ® Has Nearly Double The Nickel Content Of Other Quench & Tempered Wear Resistant Steels.

But We Don’t Stop There

At JADCO, we track every single plate of steel we receive through every job.

This tracking makes certain your QT Plus ® meets our hardness targets. There are no tricks when it comes to your wear plate performance. Just talented people paying careful attention to the details so your project is correct.


We didn’t achieve 40 years in business by selling questionable products.


We wouldn’t want it any other way.


Why Doesn’t Every Steel Company Make Their Products Last As Long As JADCO QT Plus ®?


This attention to detail from the steel mill in Pennsylvania is actually available to anyone. Yet most steel wear plate distributors choose to limit essential elements like Nickel to offer a lower price.


They do not care how long it lasts in your equipment. They are happy to continue selling you more of the same under performing material in a few months, robbing you of your hard earned profits.


For the last 40 years we have focused exclusively on delivering consistent, longer life for our customers.


Now you understand why we get better results. We think differently and focus only on your results.


Allow us to help you today by calling (724) 452-5252, or email sales@jadcomfg.com.


We will schedule a meeting with one of our local wear plate specialists at a time that best fits your schedule.


Remember, the only thing you have to lose by not working with JADCO, are your profits.

When your AR steel gives out, give JADCO a shout!