AISI 430 steel

The distinction between martensitic steels and other steels is not sharp. Some ferritic stainless steels such as AISI 430 steel (UNS S4300) or the 3Cr 12 alloy (UNS S41003), can be partially martensitic. Conversely, low-carbon martensitic steels such as AISI 410S (UNS 41008) and 416 (UNS S41603) might substantially ferritic. The lower chromium alloy content steels such as AISI 500 series heat-resistant steels also have many characteristics of martensitic steels. 

The effect of the ahoying elements on AISI steels is indirect because ahoying elements control microstmcture through their effect on hardenabhity. These elements permit the attainment of desirable microstmctures and properties over a much wider range of sizes and sections than is possible with carbon steels. 

TABLE 28-7 Properties of Low-Alloy AISI Steels Concluded)... 

Examples of types of SAE and AISI steel are provided in TABLE 9-2. 

Figure 6.14. Comparison of corrected model prediction with crack growth data on AISI steel at 413 K [3].

Waveguides 4 waveguides (points 5L-8L,. I), made of AISI 304 stainless steel, L = variable, (j>=6 mm, have been installed on the lower body of the SH header of unit 3 and 8 waveguides (points 2A-5A and points 2P-5P,y5. 2), made of AISI 304 stainless steel, L = 3240 mm, if>=6 mm, have been installed on the front (4 waveguides) and rear (4 waveguides) bodies of the SH header of unit 4. 

Mating material AISI 1018 Steel, Rc20,16AA 689 kPa = 100 psi. 

Unfilled Teflon PFA has been tested in mechanical appHcations using Teflon FEP-100 as a control (24). Tests were mn on molded thmst bearings at 689.5 kPa (100 psi) against AISI 1080, Rc 20,16AA steel, and at ambient conditions in air without lubrication. A limiting PV value of 5000 was found. Wear factors and dynamic coefficients of friction are shown in Table 4. 

Many initiators attack steels of the AISI 4300 series and the barrels of the intensifiers, which are usually of compound constmction to resist fatigue, have an inner liner of AISI 410 or austenitic stainless steel. The associated small bore pipework and fittings used to transfer the initiator to the sparger are usually made of cold worked austenitic stainless steel. The required pumping capacity varies considerably from one process to another, but an initiator flow rate 0.5 L / min is more than sufficient to supply a single injection point in a reactor nominally rated for 40 t/d of polyethylene. 

Fig. 8. Stress—rupture curves for annealed H-grade austenitic stainless steels. AISI numbers are given (see Table 3). Rupture iu 10,000 h (35). To convert...

Steels iu the AISI 400 series contain a minimum of 11.5% chromium and usually not more than 2.5% of any other aHoyiag element these steels are either hardenable (martensitic) or nonhardenable, depending principally on chromium content. Whereas these steels resist oxidation up to temperatures as high as 1150°C, they are not particularly strong above 700°C. Steels iu the AISI 300 series contain a minimum of 16% chromium and 6% nickel the relative amounts of these elements are balanced to give an austenitic stmcture. These steels caimot be strengthened by heat treatment, but can be strain-hardened by cold work. 

AISI 321 and 347 are stainless steels that contain titanium and niobium iu order to stabilize the carbides (qv). These metals prevent iatergranular precipitation of carbides during service above 480°C, which can otherwise render the stainless steels susceptible to iatergranular corrosion. Grades such as AISI 316 and 317 contain 2—4% of molybdenum, which iacreases their creep—mpture strength appreciably. In the AISI 200 series, chromium—manganese austenitic stainless steels the nickel content is reduced iu comparison to the AISI 300 series. 

The highly aHoyed austenitic stainless steels are proprietary modifications of the standard AISI 316 stainless steel. These have higher creep—mpture strengths than the standard steels, yet retain the good corrosion resistance and forming characteristics of the standard austenitic stainless steels. Nickel-Base Superalloys. 

Because of the low viscosities of cryogenic Hquids, rolling element bearings seem better suited than hydrodynamic bearings for turbo pumps. AISI 440C stainless balls and rings generally are preferred for their corrosion resistance over the more commonly used AISI 52100 steel. 

Steels Products Manual—Elat Rolled Electrical Steel, American Iron and Steel Institute (AISI), Washington, D.C., 1978. 

Table 3. Standard Numerical AISI-SAE Designations of Plain Carbon and Constructional Alloy Steels...

The AISI (American Iron and Steel Institute) and the SAE (Society of Automotive Engineers) specifications are essentially the same. The Hst is simplified to show typical compositions. Eor ranges, see original tables. 

In identifying a particular steel, the letters x are replaced by two digits representing average carbon content. Eor example, an AISI 1040 steel would have an average carbon content of 0.40%, with a tolerance of 0.03%, giving a range of 0.37—0.44% carbon. 

---