| YST Alloy (Corrosion and wear resistant special stainless steel casting) YOKOTA's special stainless steel casting, YST series, with enhanced pitting and crevice corrosion resistance as well as wear resistance, has been favorably received as a standardized material suitable for pumps and valves in equipment for anti-pollution treatment, seawater treatment, and chemical processing among others.
In particular, this YST Alloy has been adopted as the pump material for wet-type smoke discharging desulfurizers under a variety of severely corrosive and abrasive conditions, proving its excellent durability and reliability even under severe conditions.
Moreover, YOKOTA's duplex stainless steel YST130N, not only shows outstanding seawater resistance, but also is applicable to many different types of liquid as an excellent corrosion and wear resistant material. |
Characteristics of YST Alloy Compared with JIS materials such as SCS13, SCS14, and Carpenter 20 (SCS23), a widely used corrosion resistant material, YST Alloy has the following advantages: | 
| Excellent corrosion resistance, and especially effective against local corrosion due to chloric ion conditions. |
| Improved wear resistance due to improved hardness, resulting in both corrosion resistance and wear resistance. |
| Excellent resistance to pitting and crevice corrosion in seawater. |
| Outstanding strength (nearly twice as strong as general JIS materials). |
| Easily welded by covered arc or TIG welding without preheating or residual heating. |
 | | Fluorescence X-ray spectroscopy system |
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Applications of YST Alloy | | Wet-type flue gas desulfurizer drainage treatment system | | |
| Acid-containing drainage treatment system for semiconductor plant | | |
| Incinerator drainage treatment system | | |
| | | Boiler/Scrubber circulating system | | |
| Seawater desalination system | | |
| | Pulp and paper process water | | |
| Electroplating wastewater | | |
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Wear resistant high Cr steel casting Developed for sand pump material, wear resistant high Cr steel casting (CCR10) is used in pumps for construction work, sedimentation ponds, and also used in pumps to treat lime-gypsum liquid and other high density, slurry liquid. |
Chemical composition
| Metallographic structure | Material | Chemical composition | | C | Si | Mn | Ni | Cr | Mo | Others | YOKOTA
material | Austenite | YST20 | <=0.05 | <=1.5 | <=1.5 | 10-14 | 17-20 | 2-4 | Special elements | | YST30 | <=0.05 | <=1.5 | <=1.5 | 16-18 | 18-21 | 4-6 | Special elements | | YST40 | <=0.05 | <=1.5 | <=1.5 | 23-27 | 18-22 | 5-7 | Special elements | | Duplex | YST130A | <=0.05 | 0.8-1.5 | <=1.5 | 6-8 | 25-28 | 2-4 | Special elements | | YST130B | <=0.05 | 0.8-1.5 | <=1.5 | 6-8 | 25-28 | 2-4 | Special elements | | YST130N | <=0.05 | <=1.5 | <=1.5 | 6-8 | 25-28 | 2-4 | Special elements | | High chromium | CCR10 | <=2.5 | <=1.5 | <=1.5 | 0 | 14-18 | 0 | Special elements | JIS material
(for reference) | Duplex | SCS10 | <=0.03 | <=1.5 | <=1.0 | 4.5-8.5 | 21-26 | 2.5-4 | 0N 0.08-0.3 | | SCS11 | <=0.08 | <=1.5 | <=1.0 | 4-7 | 23-27 | 1.5-2.5 | | | Austenite | SCS14 | <=0.08 | <=2.0 | <=2.0 | 10-14 | 17-20 | 2-3 | 0 | | SCS23 | <=0.07 | <=2.0 | <=2.0 | 27.5-30 | 19-22 | 2-3 | Cu3-4 |
Mechanical properties
| Metallographic structure | Material | Tensile strength | Durability | Elongation | Hardness | | (N/mm2) | (N/mm2) | (%) | (Hv) | YOKOTA
material | Austenite | YST20 | >=585 | >=390 | >=10 | 200-250 | | YST30 | >=585 | >=390 | >=10 | 200-250 | | YST40 | >=585 | >=390 | >=10 | 200-250 | | Duplex | YST130A | >=735 | >=540 | >=10 | 300-350 | | YST130B | >=685 | >=490 | >=5 | 350-400 | | YST130N | >=635 | >=440 | >=10 | 250-300 | | High chromium | CCR10 | >=635 | - | - | 450-600 | JIS material
(for reference) | Duplex | SCS10 | >=620 | >=390 | >=15 | <=319 | | SCS11 | >=590 | >=345 | >=13 | <=253 | | Austenite | SCS14 | >=440 | >=185 | >=28 | <=192 | | SCS23 | >=390 | >=165 | >=30 | <=192 |
Corrosion resistance, Wear resistance
Fig.1 All-surface corrosion resistance |  |
Fig.2 Pitting corrosion resistance |  |
As Fig.1 and 2 show, YST Alloy has excellent local corrosion resistance especially to liquids containing chloric ion, in addition to all-surface corrosion resistance. Fig.3 shows that YST Alloy also has excellent wear resistance, thus being suitable for various kinds of liquid.
Fig.3 Corrosion resistance and wear resistance |  |
Fig.4 Wear resistance (Rate of wear, counting the wear of SUS316 by 20% slurry as 100) |  |
Fig.5 Corrosion resistance and wear resistance (Rate of wear, counting the wear of SUS316 by 5% slurry as 100) | 
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YST130N is more suitable than YST130A for highly corrosive slurry liquid.
| Features | Structure | Technical data | Selection & Dimensions | Inquiry form |
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