+0086-574-89017168
Call Us
Call Us
fuchun@fu-chun.com
Send me an inquiry
Send me an inquiry
9:00-18:00
Monday - Friday
Monday - Friday
- All
- Product Name
- Product Keyword
- Product Model
- Product Summary
- Product Description
- Multi Field Search
H1. 1. Precision casting surface non-destructive sand cleaning equipment is easy to operate with high efficiency.H2. 2. The special shape and hole cavity of the casting has good deoxidization treatment effect, standard nozzle is suitable for small deoxidization, equipped with high pressure on the no
2018.05.27
Read MoreH2. As we all know, at ordinary times in the casting, accidentally will produce the die. The formation of scrap not only delays the staff's time, but also wastes the material of the module. But now advocate of saving energy production in China, under the influence of national policy, now many of the
2018.05.14
Read MoreH2. 1.Process planning:Strictly control the process, before the tanks, to ensure that the appearance and the sand core is with temperature condition, to ensure when pouring molten steel liquid, on appearance coarse broken place choose luck gentleman family ISOMOL300 alcohol-based zircon powder coati
2018.04.12
Read MoreH2. 1.Holding timeThe length of holding time depends on the precision casting material and wall thickness.For castings with high melting point, high crystallization temperature range and thick wall, the holding time is longer.For the casting of small and thin wall of crystallization temperature, the
2018.04.09
Read MoreSand type precision casting is preferred.According to statistics, in our country or international, in total casting production, 60 ~ 70% of casting is made of sand,and about 70% of them are made of clay sand.The main reason is that sand casting is cheaper than other casting methods、the production pr
2018.04.07
Read MoreIn the process of using stainless steel precision casting, its temperature can guarantee that its melt has good fluidity in the process of transfer，In the process of selecting temperature, the stainless steel precision casting needs to be determined according to the distance of the transfer and the
2018.04.03
Read MorePrecision casting technology can be summarized in developed countries to protect the environment, improve casting quality and reliability, reduce production cost and shorten delivery time.Ductile iron casting technology as an important part of casting technology, research on ductile cast iron castin
2018.03.31
Read MoreThis is where a batch of steel meets more than one specification or grade. It is a way of allowing melting shops to produce stainless steel more efficiently by restricting the number of different types of steel. The chemical composition and mechanical properties of the steel can meet more than one grade within the same standard or across a number of standards. This also allows stockholders to minimise stock levels.
For example, it is common for 1.4401 and 1.4404 (316 and 316L) to be dual certified - that is the carbon content is less than 0.030%. Steel certified to both European and US standards is also common.
There are many different types of surface finish on stainless steel. Some of these originate from the mill but many are applied later during processing, for example polished, brushed, blasted, etched and coloured finishes.
The importance of surface finish in determining the corrosion resistance of the stainless steel surface cannot be overemphasised. A rough surface finish can effectively lower the corrosion resistance to that of a lower grade of stainless steel.
Various types of stainless steel are used across the whole temperature range from ambient to 1100 deg C. The choice of grade depends on several factors:
In the European standards, a distinction is made between stainless steels and heat-resisting steels. However, this distinction is often blurred and it is useful to consider them as one range of steels.
Increasing amounts of Chromium and silicon impart greater oxidation resistance. Increasing amounts of Nickel impart greater carburisation resistance.
Austenitic stainless steels are extensively used for service down to as low as liquid helium temperature (-269 deg C). This is largely due to the lack of a clearly defined transition from ductile to brittle fracture in impact toughness testing.
Toughness is measured by impacting a small sample with a swinging hammer. The distance which the hammer swings after impact is a measure of the toughness. The shorter the distance, the tougher the steel as the energy of the hammer is absorbed by the sample. Toughness is measured in Joules (J). Minimum values of toughness are specified for different applications. A value of 40 J is regarded as reasonable for most service conditions.
Steels with ferritic or martensitic structures show a sudden change from ductile (safe) to brittle (unsafe) fracture over a small temperature difference. Even the best of these steels show this behaviour at temperatures higher than -100 deg C and in many cases only just below zero.
In contrast austenitic steels only show a gradual fall in the impact toughness value and are still well above 100 J at -196 deg C.
Another factor in affecting the choice of steel at low temperature is the ability to resist transformation from austenite to martensite.
It is commonly stated that “stainless steel is non-magnetic”. This is not strictly true and the real situation is rather more complicated. The degree of magnetic response or magnetic permeability is derived from the microstructure of the steel. A totally non-magnetic material has a relative magnetic permeability of 1. Austenitic structures are totally non-magnetic and so a 100% austenitic stainless steel would have a permeability of 1. In practice this is not achieved. There is always a small amount of ferrite and/or martensite in the steel and so permeability values are always above 1. Typical values for standard austenitic stainless steels can be in the order of 1.05 – 1.1.
It is possible for the magnetic permeability of austenitic steels to be changed during processing. For example, cold work and welding are liable to increase the amount of martensite and ferrite respectively in the steel. A familiar example is in a stainless steel sink where the flat drainer has little magnetic response whereas the pressed bowl has a higher response due to the formation of martensite particularly in the corners.
In practical terms, austenitic stainless steels are used for “non-magnetic” applications, for example magnetic resonance imaging (MRI). In these cases, it is often necessary to agree a maximum magnetic permeability between customer and supplier. It can be as low as 1.004.
Martensitic, ferritic, duplex and precipitation hardening steels are magnetic.