Due to the presence of ferrite and austenite in the structure of duplex stainless steel, it has the higher strength of ferritic stainless steel, resistance to chloride stress corrosion and the excellent toughness and welding of austenitic stainless steel Advantages of performance. Its main performance characteristics are as follows:
(1) The duplex stainless steel containing molybdenum has good resistance to chloride stress corrosion under low stress.
(2) The duplex stainless steel containing molybdenum has good pitting corrosion resistance. When they have the same pitting resistance equivalent value (PRE=Cr%+3.3xMo%+16xN%). The critical pitting potential of duplex stainless steel is similar to that of austenitic stainless steel. The corrosion resistance of duplex stainless steel and austenitic stainless steel is equivalent to ANSI 316L. Containing 25%Cr. Especially nitrogen-containing high-chromium duplex stainless steel has pitting and crevice corrosion resistance exceeding ANSI316L.
(3) Has good resistance to corrosion fatigue and wear and corrosion.
(4) The comprehensive mechanical properties are good, with higher strength and fatigue strength, and the yield strength is twice that of 18-8 austenitic stainless steel. The elongation in solid solution reaches 25%, and the toughness value Ak (V-notch) is above 100J.
(5) Good weldability, small tendency to hot cracking, no preheating before welding, and no heat treatment after welding. It can be welded with different types of 18-8 austenitic stainless steel or carbon steel.
(6) The hot working temperature range of duplex stainless steel containing low chromium (18%Cr) is wider than that of 18-8 austenitic stainless steel, and the resistance is smaller.
(7) The work-hardening effect of cold JJD-r is greater than that of 18-8 austenitic stainless steel. In the early stage of deformation of the tube and plate, a large stress needs to be applied to deform.
(8) Compared with austenitic stainless steel, the thermal conductivity is large and the linear expansion coefficient is small.
(9) There are various brittleness tendency of high chromium ferritic stainless steel. It should not be used in working conditions higher than 300°C.
What are the advantages of using two-phase steel valves (function: control parts) when using them (explain: the favorable situation that can overwhelm the other side)? Why there are many places where such products need to be purchased and used in order to ensure a more stable (explained: stable and stable; no changes) in the use of the effect, which has become a problem that some users want to understand.
The advantages of marine dual-phase steel valves (function: control components) (interpretation: favorable situation that can overwhelm each other) are divided into the following aspects, first of all, the performance of the product is very stable (interpretation: stable and stable; no change), in the product At the time of purchase, the user must complete the purchase of the product through a professional manufacturer. Since the manufacturer is producing and processing, whether it is the raw material used in the production and processing of the product, or the production process used in the production and processing of the product, it can be achieved in professional (professional) A relatively high level. Therefore, in the production and processing of products, as long as the products are purchased through professional manufacturers, the users can be particularly satisfied with the performance.
Secondly, in the process of using the product, the appearance of the product will be found. When designing, the manufacturer has not only developed some features of the product's functionality, but also conducted a special research (research) on the appearance of the product. Marine valves are generally used in applications where the working medium is somewhat corrosive. The ability of any valve material to withstand the corrosion of the working medium is relatively limited and is affected by many factors. If the processing technology and heat treatment technology used in the manufacturing process are proper, then the corrosion resistance of this material is guaranteed. It can ensure that the product is connected to the entire device after the installation is completed, and the appearance is beautiful.
In addition, when used for marine dual-phase steel valves (function: control parts), the purchase price can be very cheap. Stainless steel valves are made of stainless steel materials. Under the same performance conditions, the purchase cost of this professional product can be reduced to a certain extent. When users use the product, they can enjoy a relatively stable (explanation: stable and stable; no change), and can enjoy a preferential price, so they can make many users more satisfied, willing to such a product to buy.