Alloys testing

Fig. 4. Fatigue data for high temperature alloys (a) As vs cycles to failure for various alloys tested under strain control. (°) = testing at RT in air ...

Coupon tests involved a number of metallurgies and were done to evaluate precipitator-plate alloys. Test stainless steel plates failed, not only because of pitting but also because stress-corrosion cracks developed. 

It was concluded that 1.5Ti-3.0Al should be considered the most suitable alloy for ECC flue gas expander rotors. A 1,400-mm diameter expander rotor disk was manufactured using this alloy. Test specimens removed from the disk rim showed that the disk had equivalent tensile properties at both room and elevated temperatures, and the same creep rupture strength as that of AISI 685. 

Gravity die cast ZA alloy test plates and 99.99% pure rolled zinc samples were exposed at a waste water treatment plant in Detroit, Michigan, USA. The results after one year are summarised in Table 4.38 . 

Tests in thermal convection loops with a maximum temperature of 800 C showed that nickel and nickel-rich alloys with chromium and other additions were relatively very susceptible to the mass-transfer type of attack by lead. On the other hand nickel-rich alloys with molybdenum were among the better of the alloys tested (Table 7.35). 

Fig. 8.52 Initial stress intensity factor and time to failure for a susceptible titanium alloy tested in a neutral aqueous environment under plane strain conditions...

Small variations in solution composition may also affect the value of any critical velocity. In laboratory tests using recirculating artificial sea-water the presence of dissolved copper from copper alloy test-pieces has been shown to affect the value of the critical velocity for such materials . 

It should be noted that although ASTM A262 1986 provides details of test procedures no information is given on typical corrosion rates or acceptable limits for various heat-treated alloys, which are regarded as outside the province of a specification that describes test procedures. Table 19.4, taken from a paper by Brown, shows the maximum acceptable evaluation test rates specified by the Du Pont Company for various alloys tested by the acid... 

Test method for sandwich corrosion test Recommended practice for preparing, cleaning, and evaluating corrosion test specimens Practice for aqueous corrosion testing of samples of zirconium and zirconium alloys Test method for corrosion testing of products of zirconium, hafnium and their alloys in water at 633 K or in steam at 673 K [metric] Recommended practice for conventions applicable to electrochemical measurements in corrosion testing... 

Averaged valence electrons per atom for the alloy tested. 

The obvious drawback to the use of Li alloys instead of Li metal in batteries is the lower potential, specific charge, and specific energy of Li-alloy-based battery systems, compared with Li metal batteries. The work with Li alloys as alternatives for Li metal batteries began in the early 1970s [293], Table 8, taken from Ref. 294, presents some data on Li alloys tested as anodes in rechargeable Li battery systems. The various examples of Li alloys shown in Table 8 can be divided into three groups ... 

Table 8 Selected Data on Li Alloys Tested as Anodes in Rechargeable Li Battery Systems... 

The resistance of the alloys tested to crevice corrosion in 6% ferric chloride is as follows ... 

Figure 2. Mechanical properties of a new superhigh strength A1 alloy tested in the T6 temper. See [11 ] in this volume for more details.

Figure 4. FEGSEM micrographs of the fracture surfaces of Zr-stabilized 2014 aluminum alloy tested at 125 MPa failured after 3.5 105 Cycles.

Figure 6. Regions of stable crack growth and overload observed in the Zr-stabilized 2014 aluminum alloy tested at 115 MPa...

Figure 7.9. Constant load-amplitude fatigue crack growth curves for a mill-annealed T1-6A1-4V alloy tested in vacuum at room temperature [4],...

The corrosion resistance of various metals and alloys in high-temperature liquid lithium is shown in Figure 11. Unfortunately, lithium is much more corrosive than sodium. Consequently, it will be impossible to take full advantage of its many attractive heat-transfer properties until a satisfactory container material is found. The most corrosion-resistant pure metals in a static isothermal system are molybdenum, niobium, tantalum, tungsten, and iron. Of the commercially available structural materials, no alloys tested to date have had satisfacto corrosion resistance at a temperature above 1400 F. for extended time periods in systems where temperature differentials exist. Even though iron has good resistance in static isothermal lithium, iron and iron-base alloys suffer from mass trans-... 

Properties of friction stir welds in all of the alloys tested appear to be excellent. In some cases, they exceed the properties of the base metal. In virtually all cases, they exceed the properties of alternative fusion welding processes. Further, FSW has been demonstrated to produce lower distortion than GMAW and SAW in the welding of 13 mm thick HSLA-65 steel. 

In some cases a measure of the reaction kinetics is not as useful as a measure of the useful life under a given set of experimental conditions. Cyclic oxidation tests using weight-change versus time measurements and visual examination of exposed specimens can be useful to determine times beyond which protective scales, such as alumina, are no longer formed on alloy test coupons. 

With decreasing temperature the alloys exhibited some decrease in notch strength and notch yield ratios the amount of the decrease varied with composition and temper. The plots of the ratios as functions of temperature in Fig. 2 are smooth curves, with no suggestion of abrupt transitions in fracture behavior. The data for those alloys that were tested only at temperatures to —320°F may be compared readily with those for alloys tested down to —423°F, with little likelihood of misinterpretation. 

Watson, W., Short Time Properties of Advanced Alloys Tested at CANEL., Pratt and Whitney Aircraft- CANEL., April 20, 1965. 

This paper summarizes the experimental results on the fatigue crack growth resistance of 14 commercial structural alloys tested at selected temperatures between 295 and 4 K. Many of the results are reported here for the first time some data were previously reported [% The comparisons made in this paper lead to generalizations showing that temperature effects on da/dN vs. AAT behavior can be correlated with alloy crystal structure. 

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