Low temperature resistant ductile iron rod 65-45-12

Low temperature resistant ductile iron rod imported ductile iron rod, imported ductile iron plate, imported ductile iron square rod, Japan imported ductile iron rod, Japan imported ductile iron plate, high wear resistant ductile iron rod, high temperature resistant ductile iron plate, high strength ductile iron Rods, large diameter ductile iron round rods, gray cast iron rods, gray cast iron round rods, imported gray cast iron plates, corrosion-resistant ductile iron, comparison table of ductile iron grades in various countries, Xiangyun ductile iron wholesale, imported ductile iron, imported gray cast iron, imported Gray cast iron rod, ductile iron material certificate, chemical composition of ductile iron, ductile iron price, gray cast iron price, rust-proof cast iron, austenitic cast iron, Dongguan Xiangyun ductile iron. Sales Hotline
: Manager Liu-:.
Ductile Iron
A general term for alloys mainly composed of iron, carbon and silicon. These alloys contain more carbon than can be retained in the austenite solid solution at the eutectic temperature. Cast iron is a general term for alloys mainly composed of iron, carbon and silicon. These alloys contain more carbon than can be retained in the austenite solid solution at the eutectic temperature.
Iron-carbon alloy with carbon content above %. Industrial cast iron generally contains % to % carbon. Carbon mostly exists in the form of graphite in cast iron and sometimes in the form of cementite. In addition to carbon, cast iron also contains % to % of silicon and elements such as manganese, phosphorus, and sulfur. Alloy cast iron also contains elements such as nickel, chromium, molybdenum, aluminum, copper, boron, and vanadium. Carbon and silicon are the main elements that affect the microstructure and properties of cast iron.
Cast iron can be divided into
① Gray cast iron. The carbon content is relatively high (.%~.%), and the carbon mainly exists in the form of flake graphite. The fracture surface is gray and is referred to as gray iron. Low melting point (~℃), small shrinkage during solidification, compressive strength and hardness close to carbon steel, and good shock absorption. Used to manufacture machine tool beds, cylinders, boxes and other structural parts.
②White cast iron. The carbon and silicon content are low, and the carbon mainly exists in the form of cementite and the fracture surface is silvery white. It shrinks greatly during solidification and can easily cause shrinkage holes and cracks. High hardness and brittleness cannot withstand impact loads. It is mostly used as a blank for malleable iron and to make wear-resistant parts.
③ Malleable cast iron. After annealing white cast iron, the graphite is distributed in a flocculent form, which is referred to as tough iron. Its structural properties are uniform, wear-resistant, and has good plasticity and toughness. Used to manufacture parts with complex shapes that can withstand strong dynamic loads.
④ Ductile iron. After the gray cast iron molten iron is spheroidized, the precipitated graphite is spherical, which is referred to as ductile iron. It has higher strength, better toughness and plasticity than ordinary gray cast iron. Used in the manufacture of internal combustion engines, auto parts, agricultural machinery, etc.
⑤Vermicular graphite cast iron. After the gray cast iron molten iron is vermiformed, the precipitated graphite is obtained in the shape of worms. The mechanical properties are similar to ductile iron, and the casting performance is between gray cast iron and ductile iron. Parts used in manufacturing automobiles.
⑥Alloy cast iron. Ordinary cast iron is obtained by adding appropriate amounts of alloying elements (such as silicon, manganese, phosphorus, nickel, chromium, molybdenum, copper, aluminum, boron, vanadium, tin, etc.). Alloying elements change the matrix structure of cast iron to have corresponding heat resistance, wear resistance, corrosion resistance, low temperature resistance or non-magnetic properties. Used to manufacture parts for mining, chemical machinery, instruments, meters, etc.
⑦Austenitic cast iron. There are two types of cast iron, austenitic gray cast iron and austenitic ductile iron, which are made by smelting iron, carbon, nickel and adding elements such as silicon, manganese, copper and chromium. The cast iron is mainly austenitic and has a stable austenite matrix at room temperature.
Classification of cast iron
Classification method Classification name description
.Classified by fracture color
Gray cast iron Most or all of the carbon in this type of cast iron is in the form of free state flake graphite. Its fracture surface is dark gray, has certain mechanical properties and good cutting properties, and is widely used in industry
White cast iron White cast iron is an iron-carbon alloy with no or almost no graphite in the structure. Its fracture surface is The bright white color is hard and brittle and cannot be cut. It is rarely used directly in industry to make mechanical parts. Because of its high surface hardness and wear resistance, it is also called chilled cast iron or chilled cast iron
Mock cast iron Mock iron is a kind of cast iron between white cast iron and gray cast iron. Its fracture is gray-white Alternate pitting has poor performance and is rarely used
. Classified by chemical composition
Ordinary cast iron refers to cast iron that does not contain any alloying elements, such as gray cast iron, malleable cast iron, ductile iron, etc.
Alloy cast iron It is a high-grade cast iron prepared by adding some alloying elements to ordinary cast iron to improve certain special properties. Such as various corrosion-resistant, heat-resistant, wear-resistant cast irons with special properties
. According to production methods and organizational properties
Ordinary gray cast iron, see gray cast iron
Breeding cast iron is based on gray cast iron It is made of modified cast iron, also known as modified cast iron. Its strength, plasticity and toughness are much better than ordinary gray cast iron, and its structure is also more uniform. Mainly used to manufacture large castings that require high mechanical properties and large changes in cross-sectional dimensions
Malleable cast iron Malleable cast iron is made from white cast iron with a certain composition that has been graphitized and annealed. It has higher toughness than gray cast iron and is also called ductile cast iron. . It cannot be forged and is commonly used to make castings that can withstand impact loads
Ductile iron is referred to as ductile iron. It is obtained by adding a certain amount of nodularizing agent and inking agent to the molten iron before casting to promote the crystallization of spheroidal graphite. Compared with steel, except for slightly lower plasticity and toughness, it has almost all other properties. It is an excellent material that combines the advantages of steel and cast iron. It is widely used in mechanical engineering
Special performance cast iron This is a cast iron with certain characteristics. Different uses can be divided into wear-resistant cast iron, heat-resistant cast iron, corrosion-resistant cast iron, etc. Most of them belong to alloy cast iron and are widely used in machinery manufacturing
Cast iron - heat treatment process
. Stress relief annealing. Due to the uneven wall thickness of the casting, effective stress and structural stress will be generated during the heating, cooling and phase transformation processes. In addition, large parts are prone to residual stress after machining. All these internal stresses must be eliminated. The usual heating temperature for stress relief annealing is ~°C and the holding time is ~~ and then furnace cooling (gray iron) or air cooling (ductile iron). Using this process can eliminate ~% of the internal stress of the casting without changing the cast iron structure. If the temperature exceeds ℃ or the holding time is too long, it will cause graphitization and reduce the strength and hardness of the casting.
.High-temperature graphitization annealing to eliminate cast iron white spots
White spots often occur on the surface and thin sections of castings when they are cooled. The white structure is hard and brittle, has poor processing performance and is easy to peel off. Therefore, annealing (or normalizing) must be used to eliminate the white structure. The annealing process is: heating to -℃, keeping warm, then cooling the furnace to -℃ and then leaving the furnace for air cooling. During the high-temperature holding period, high-temperature cementite and eutectic cementite decompose into graphite, and during the subsequent cooling process, secondary cementite and eutectoid cementite also decompose and graphitize. Due to the decomposition of cementite, the hardness decreases and the machinability is improved.
.Normalizing of ductile iron
The purpose of normalizing ductile iron is to obtain the pearlite matrix structure and refine the uniform grain structure to improve the mechanical properties of the casting. Sometimes normalizing is also the structural preparation for surface quenching of ductile iron. Normalizing is divided into high-temperature normalizing and low-temperature normalizing. The high-temperature normalizing temperature generally does not exceed ~℃. The low-temperature normalizing temperature is generally heated to the co-folding temperature range ~℃. After normalizing, four people are generally required to handle it to eliminate the internal stress generated during normalizing.
.Quenching and tempering of ductile iron
In order to improve the mechanical properties of ductile iron, castings are generally heated to above ~°C (representing the final temperature of formation during heating) and then quenched in oil to obtain a martensite structure. In order to appropriately reduce the residual stress after quenching, tempering should generally be carried out after quenching. The low-temperature tempering structure is tempered martensite plus residual bainite plus spherical graphite. This kind of structure has good wear resistance and is used for parts that require high wear resistance and high strength. The medium temperature tempering temperature is -℃. The structure after tempering is tempered troostite plus spherical graphite. It is suitable for thick parts that require good wear resistance, certain stability and elasticity. Xiangyun Company-Relevant talents are mostly concentrated in the Steel Talent Network. The high temperature tempering temperature is -D℃. The structure after tempering is tempered Soxhlet plus spherical graphite, which has a good combination of toughness and strength. The structure after tempering is -D℃. The structure after tempering is tempered Soxhlet plus spherical graphite, which has a combination of toughness and strength. Good comprehensive performance makes it widely used in production.
.Multi-temperature quenching of ductile iron
After isothermal quenching, ductile iron can obtain high strength and good plasticity and toughness. The main consideration in selecting the heating temperature for multi-temperature quenching is to ensure that the original structure is completely intact, without residue, and to avoid grain growth. The heating temperature is generally used above ~°C and the isothermal treatment temperature is ~°C to ensure that a lower bainite structure with comprehensive mechanical properties is obtained. After isothermal quenching of rare earth magnesium aluminum ductile iron =~=~./r~. However, it should be noted that a tempering process is added after isothermal quenching.
.Surface quenching
In order to improve the surface hardness, wear resistance and fatigue strength of some castings, surface quenching can be used. Both gray cast iron and ductile iron castings can be surface quenched. Generally, high (medium) frequency induction heating surface quenching and electrical contact surface quenching are used.
.Chemical heat treatment
For castings that require surface wear resistance, oxidation resistance, and corrosion resistance, chemical heat treatment processes similar to steel can be used, such as gas soft chlorination, chlorination, boronization, sulfurization, etc.
Gray cast iron
China
Japan
Korea
United States
United States
Ductile iron
China-
Japan
/> Korea DDD
United States -------
United States
Features: Complete product specifications, favorable price, good packaging, good straightness, large inventory, and can provide material certificates and reports.
Special specifications can be customized. Xiangyun Company welcomes your call and we will serve you sincerely. Sales Hotline
: Manager Liu-:.
Beijing ductile iron rod Tianjin ductile iron rod Hebei ductile iron rod Shanxi ductile iron rod Inner Mongolia ductile iron rod Hainan ductile iron rod
Liaoning ductile iron rod Jilin ductile iron rod Heilongjiang ductile iron rod Shanghai ductile iron rod Jiangsu ductile iron rod Cast iron rod Chongqing ductile iron rod
Zhejiang ductile iron rod Anhui ductile iron rod Fujian ductile iron rod Jiangxi ductile iron rod Shandong ductile iron rod Sichuan ductile iron rod
Henan ductile iron rod Hubei ductile iron rod Hunan ductile iron rod Guangdong ductile iron rod Guangxi ductile iron rod Guizhou ductile iron rod
Yunnan ductile iron rod Tibet ductile iron rod Shaanxi ductile iron rod Gansu ductile iron rod Qinghai ductile iron rod Ningxia ductile iron rod
Xinjiang ductile iron rod Hong Kong ductile iron rod Cast iron rods Macau ductile iron rods Taiwan ductile iron rods other ductile iron rods