What Material Is Nihard4 Made of?

Corrosion-resistant nickel is a kind of high nickel metal that is resistant to acid and corrosive salt solutions. Corrosion-resistant nickel has an austenitic structure matrix and is an alloy containing nickel and about 10% carbide. It comes in 2 forms: Type 1 (201) and type 2 (202); The former is readily available and most common, while the latter is suitable for special applications with high temperature requirements (1300oF).

Nickel has excellent heat resistance, corrosion resistance, and abrasion resistance, and will not be magnetized while maintaining its mechanical properties. It is suitable for wear-resistant parts in aluminum components, such as cylinder heads in aluminum pistons and valve guides in ring seats, because it has the same expansion coefficient as aluminum.

The most common applications are seawater, sulfuric acid, hydrochloric acid environments, and parts used in petroleum refining.

3. Does Ni-Hard 1 Iron Break Easily? Is It Cast Steel or Cast Iron?

Nickel hard cast iron, BHN600 or so, hard and brittle, heat treatment can improve the impact toughness and martensitic matrix.

4. What Are The Classifications Of White Cast Iron?

In the crystallization process, there is no graphite precipitation, the fracture is silver-white cast iron, referred to as white iron. The tissue contains more free cementite, which has a high hardness (generally above HB500), but is brittle, and is mostly used as anti-wear parts, such as farm tools, grinding balls, coal mill parts, shot blasting machine blades, mud pump parts, cast sand pipes and the outer surface of chilled rolls.

4.1 Ordinary White Cast Iron:

As early as the Spring and Autumn Periods, China made white cast iron with good wear resistance and used it as some anti-wear parts. This kind of cast iron has the characteristics of high carbon and low silicon, and has a high hardness, but is very brittle, suitable for the manufacture of small impact load parts, generally used in plowshare, grinding plate, guide plate, and so on. Heat treatment is often used in production to improve its performance and expand its application range.

Carbon plays the most important role in the wear resistance of ordinary white cast iron, the higher the carbon content, the more cementite is formed, forming a large number of Letenite, so the higher the hardness, the better the wear resistance. But the carbon content is high, the toughness is reduced. The number and distribution of cementites should be selected according to the specific working conditions of the parts.

Generally, the hardness of ordinary white cast iron is in a straight line relationship with the carbon content, that is, HS=16.7C+13 (HS – Shore hardness; C – the percentage of carbon content).

4.2 Low Alloy White Cast Iron:

Adding a small amount of alloying elements to ordinary white cast iron can increase the microhardness of carbide, strengthen the metal matrix, and thus improve the wear resistance. White cast iron containing chromium, molybdenum, copper, and other elements is usually melted by a cupola, mostly used in the cast state, so the cost is lower.

However, the carbides in the metallographic structure of this white cast iron are still a continuous network, so the brittleness is still large, and it is suitable for occasions where the wear resistance and toughness are not too high. Adding boron 0.15% ~ 0.55%, boron mainly into the carbide can also improve the wear resistance.

4.3 Medium Alloy White Cast Iron:

With chromium as the main alloying element, when the amount of chromium is added to 9%, the (Cr, Fe) 7C3 carbide appears in the organization, and its hardness is as high as 1300 ~ 1800HV. This kind of carbide is isolated rod or plate shape, poor continuity, so good toughness, and high strength. In addition to chromium, medium alloy white cast iron has:

(1) Nickel hard white cast iron, International Nickel Company’s brand has Ni-Hard1, 2, 3, 4 four kinds. The nickel content is between 3% and 5%, and the chromium content can be divided into two kinds: 2%Cr and 9%Cr. The former carbide is (Fe, Cr) 3C, with a hardness of 1100 ~ 1150HV, which is higher than the hardness of Fe3C of 900 ~ 1000HV. The latter is mostly (Cr, Fe) 7C3, with higher hardness.

Ni-Hard1, 2, 3 three contain 2%Cr this category, the difference is mainly the difference in carbon content, carbon high wear resistance, and poor toughness; Low carbon is the opposite. Inco also has two special materials: high-carbon Ni-Hard4, which has high wear resistance and low impact fatigue life; Another boron-containing Ni-Hard1, the boron content is 0.25% ~ 1.0%, boron can make the hardness of martensitic matrix up to 1000HV, this material is used for castings with simple impact load.

(2) Manganese white cast iron has a high manganese content that inhibits pearlite and stabilizes austenite. There is a certain amount of martensite in the tissues, but more residual austenite. The manganese content of this cast iron is 5% to 8%, the cost is low, but the wear resistance is low, and the casting performance is poor.

(3) Manganese tungsten white cast iron, China manganese tungsten No. 1 wear-resistant cast iron for parts requiring mechanical processing; Manganese tungsten No. 2 wear-resistant cast iron has high hardness. Usually, both are used as cast.

(4) Tungsten chromium white cast iron, China has W5Cr4, W9Cr6, and W16Cr2 three grades, mainly used for impact load, low-stress erosion abrasive wear, and high-stress grinding abrasive wear occasions. Due to the high price of tungsten, the application is limited.

(5) Medium chromium white cast iron, Ni-Hard4 is a medium chromium type of white cast iron, which needs to add a large amount of valuable nickel. To save, the combined alloying of copper, molybdenum, and manganese can achieve the same purpose, and the copper content is 2% to 3%, the molybdenum content is 0.3% to 0.5%, and the manganese content is 1.5% to 2.0%. Its mechanical properties are similar to those of Ni-Hard4.

4.4 High Alloy White Cast Iron:

The most widely used is a high chromium white cast iron with a chromium content of 12% to 20%, and a carbide of (Cr, Fe) 7C3 is formed in the tissue. High chromium white cast iron is usually subjected to high-temperature heat treatment to precipitate secondary carbides, and the austenite is transformed into martensite when cooling. High chromium white cast iron is widely used in dry grinding, such as iron-making blast furnace cups and chute liners.

United States Climax (Climax) molybdenum company has 15-3 (including 15%Cr-3%Mo), 15-2-1 (including 15%Cr-2%Mo-1%Cu) two grades. 15-3 is divided into four types according to the level of carbon content: ultra-high carbon, high carbon, medium carbon, and low carbon. Low carbon toughness and low hardness, suitable for impact loads are relatively large occasions; High carbon is used for occasions with small impact loads, showing good wear resistance.

White cast iron usually contains 2.0% to 3.6%C, 0.5% to 1.9%Si, 0.25% to 0.8%Mn, 0.06% to 0.2%S, 0.06% to 0.2%P, and the rest is Fe. White cast iron can be made by adding alloying elements such as Cr, Mo, Cu, and Al.

During solidification, according to the Fe-FE3C phase diagram, no graphite precipitation, except for a small amount of carbon dissolved in ferrite, most of the form of cementite exists in cast iron. The structure is determined by the chemical composition and cooling rate, and when the cooling rate is large enough, it is a white cast iron structure.

As the cooling rate decreases, the microstructure of cast iron changes to mote cast iron, pearlitic gray cast iron, pearlitic ferritic gray cast iron, and ferritic gray cast iron in turn. White cast iron contains a large number of free carbides, high hardness, HB up to 500 or more, and toughness is very poor. In the production of cast iron, it is required to avoid producing pitted or white cracks.

White cast iron is only used to make wear-resistant farm tools, grinding balls, blades, pumps, rolls, etc. It is mainly used for the production of malleable cast iron and as a raw material for steelmaking.

What Material Is Nihard4 Made of?