Automobile Water Glass Lost Wax Casting

Product Description

The automotive industry is the largest application area for castings. Driven by factors such as the elimination of National III automobiles, the tightening of overrun control and infrastructure investment, the production and sales of commercial vehicles in 2020 will show a substantial increase, which will become an important driving force for the recovery of the auto market in 2020; Production increased, with 15 million tonnes, or 28.9% of total casting production.

After more than ten years of precipitation, Qinhuangdao Zhongwei Precision Machinery Co., Ltd. has rich production experience in Automobile water glass lost wax casting, lost foam precision casting, silica sol precision casting, and shell sand casting. We expect manufacturers from all over the world to consult and negotiate business.

Common Materials

1. Automobile water glass wax lost casting

The representative gray iron casting in automobiles is the cylinder block, and its development direction is thin-walled and high-strength. There are two main ways to achieve it: one is the low-carbon equivalent process: mainly by reducing the C and Si content of gray cast iron , to improve the strength of cast iron. Its main advantages are: by changing the ingredients after the furnace, it is easy to realize and has high reliability; no or less alloying elements are used, and the cost is low; the requirements for pre-furnace treatment and operation are relatively loose. The disadvantages are also obvious: the carbon equivalent is low, the casting performance is not good, it is easy to cause shrinkage (loose) waste and increase the casting stress; the processing performance and cross-section uniformity of the casting are poor, and the thermal conductivity of the casting is affected. The second is high carbon equivalent and alloying process: mainly to keep the C and Si content of gray cast iron at a high level (wC>3.3%), by adding alloying elements such as chromium, copper, etc., to improve the strength of cast iron, At present, it is developing in the direction of multi-element microalloying to improve the strength. . The advantages are that the alloying process is relatively mature, and the strength improvement is obvious; the casting performance is good, and the tendency to form shrinkage cavities (loose) waste products is small; the processing performance and thermal conductivity of castings are good. The disadvantage is that more alloying elements are added, and the cost of castings is not only high, but poor processing may also affect the processability and leakage of castings; the requirements for pre-furnace treatment are relatively strict.

With the improvement of engine power, the performance requirements for gray cast iron are further improved, and some cylinder blocks of domestic and foreign engines have been manufactured with HT300 or even HT350. FAW Foundry has stably used HT300 to produce 6DL and Deutz engine blocks, and also reserves the production technology of HT350. In order to meet the needs of high-speed cutting of the car cylinder block, the problems of high performance and high-speed cutting of the cylinder block material were successfully solved by optimizing the smelting process, material and alloying process and other measures.

2. Ductile iron castings

In automobiles, ductile iron is mainly represented by crankshafts, camshafts, middle and rear axle housings, various brackets, casings and other parts. At present, as-cast high-strength pearlite-based ductile iron (QT700-2, QT800-2, QT800-5) and as-cast high-toughness ferritic ductile iron (QT400-18, QT400-15, QT600-10) are developing . It is mainly obtained by optimizing the smelting process, strictly controlling the content of S, P and trace elements in the original molten iron, selecting appropriate nodularizers, inoculants, alloying elements and adding methods, and strictly following the inoculation process.

FAW Foundry Co., Ltd. has the production technology of various grades of ductile iron. In order to meet the needs of the rear axle housing of trucks, it has developed the as-cast QT600-5 process. To meet the needs of car steering knuckles, as-cast QT400-18 and QT400-15 processes were developed and applied in production.

In recent years, silicon solid solution strengthened ferritic ductile iron has gradually attracted domestic attention. It was first developed and applied in Sweden, and became the Swedish national standard (SS140725) in 1998, and was subsequently incorporated into the international standard (ISO1083) in 2004. Standard GB/T 1348-2009) will be included in the normative appendix. Internationally released solid solution strengthened ferritic ductile iron grades QT 450-18, QT 500-14, QT 600-10, which have been successfully used in automobiles. The research institute of FAW Foundry Co., Ltd. has developed chassis castings, which are currently being tested and verified.

3. Compacted Graphite Iron Castings

Compacted graphite cast iron has been widely used in automotive castings such as automobile exhaust pipes and high-horsepower engine cylinder heads. The use of compacted graphite cast iron to manufacture medium and high-power engine cylinder heads can reduce the weight of the cylinder head through design on the one hand, and improve the performance of the cylinder head and improve the power of the engine on the other hand. At present, the application of vermicular graphite cast iron in high-power engine blocks is increasing. It can reduce the wall thickness, cancel the reinforcement, and reduce the weight by about 25%. It has been successfully applied in the high-power engine blocks of foreign companies such as Ford and Audi. , Domestic FAW, Jinan Heavy Truck, etc. have also reported successful applications.

The application of compacted graphite iron is mainly limited by the difficulty of stable control of its production process. SinterCast is a Swedish joint-stock company specializing in vermicular iron technology research and production equipment manufacturing. Its products (SinterCast vermicular iron production control system) have been applied on three continents (America, Europe and Asia), and are sold to 10 largest companies in the world. Eight of the automobile manufacturers provide technical support for the production of compacted graphite iron, and about 20,000 cylinder block or cylinder head products are made of compacted graphite iron every month in the world. SinterCast claims that more than 95% of the world's compacted graphite iron products are produced by the control system provided by its company.

4. Austempered ductile iron (ADI)

Austempered ductile iron has comprehensive mechanical properties with high strength, plasticity and toughness, and is generally divided into two categories, namely high-strength type with a strength of 1200-1600 N/mm2 and a high-strength type with a strength of 900-1200 N/mm2 and an elongation of 900-1200 N/mm2. About 10% high toughness type. Due to its excellent material properties, it has achieved rapid development in developed countries in Europe and the United States. ADI products have been successfully applied in truck chassis, engines and car crankshafts. In recent years, in the European market, the application of ADI in cars is increasing, accounting for 32% of the entire ADI market. In the US market, heavy and light truck ADI parts account for 51% of the total ADI market.

In the domestic automotive field, ADI parts have also been initially applied. Hubei Automobile Gear Factory produces ADI timing gears, etc. for Cummins engines. Dongfeng Motor Co., Ltd. developed a suspension for military off-road vehicle chassis. 17 suspension parts were changed from cast steel to ADI. The total weight of this series of parts was reduced from 630.62Kg to 380.66kg, with a weight reduction rate of 39.6%. The rear leaf spring bracket of FAW Group's trucks and the gear housing cover (claw) and gear housing of military vehicles have been replaced by ADI. At present, domestic heat treatment bases for isothermal quenching have been built in Changchun, Suzhou and other places.

5. Development of special cast iron

With the improvement of engine performance, the heat resistance requirements of some castings such as exhaust pipes are getting higher and higher, and high silicon molybdenum ductile iron, medium silicon molybdenum vermicular iron, and high nickel ductile iron appear successively. FAW Group's joint venture Deutz engines have applied high-silicon molybdenum ductile iron exhaust pipes in batches, and some of FAW-Volkswagen's supercharged engines have applied high-nickel ductile iron exhaust pipes in batches. In some of FAW's own brand engines, these three types Cast iron has also been used.

Post Casting Process

1. Heat treatment: annealing, carbonization, tempering, quenching, normalizing, surface tempering

2. Processing equipment: CNC, WEDM, lathe, milling machine, drilling machine, grinder, etc.;

3. Surface treatment: powder spraying, chrome plating, painting, sandblasting, nickel plating, galvanizing, blackening, polishing, bluing, etc.

Moulds and Inspection Fixtures

1. Mold service life: usually semi-permanent. (except for lost foam)

2. Mold delivery time: 10-25 days, (according to product structure and product size).

3. Tooling and mold maintenance: Zhongwei is responsible for precision parts.

Quality Control

1. Quality control: the defective rate is less than 0.1%.

2. Samples and trial run will be 100% inspected during production and before shipment, sample inspection for mass production according to ISDO standards or customer requirements

3. Testing equipment: flaw detection, spectrum analyzer, golden image analyzer, three-coordinate measuring machine, hardness testing equipment, tensile testing machine;

4. Provide after-sales service.

5. The quality can be traced back.