AlSi alloy

In order to ensure perpendicular beam incidence on the cylindrical specimen, the circular B-scan profiles were acquired by high frequency (narrow beam) transducers in a synthetic circular aperture array. From these profiles two-dimensional reflection tomograms were reconstructed using a filtered backprojection technique. Straight line propagation was assumed. Several artificial discontinuity types in a cylindrical Plexiglas (Perspex) specimen were compared with similar artificial discontinuities in a cylindrical A/Si-alloy [2]. Furthermore, examples of real discontinuities (an inclusion and a feed head) in the cylindrical AlSi-alloy are presented. 

More recently, the circular array was proposed to assess the reflectivity of cylindrical specimens [3]. First, a circular C-scan image was obtained. The total scan time was about 25 min., which does not include a relatively time consuming alignment of the specimen. From the circular C-scan image, circular B-scan profiles were chosen in specific planes. The transducer was a focused high frequency transducer with a center frequency of 25 MHz of the transducer bandwidth. This frequency corresponds to a wavelength of 0.11 mm and 0.25 mm in the Plexiglas specimen and the AlSi-alloy, respectively. Additional experimental parameters are presented in Table 1. 

Fig. 5. shows six ultrasonic reflection tomograms. Three of these are from the Plexiglas specimen (shown left) and three are from the AlSi-alloy (shown right). The tomograms are reconstructed from reflection data measured across the plane (b), (c) and (e), respectively. The dark regions indicate high reflectivity and represent specimen interfaces and discontinuities. 

Fig. 100. The analysis of Al and AlSi alloys by spark ablation coupled with ICP-OES. 3 kW argon-nitrogen I CP, Spectrovac 1000 and 1 kV spark at 25 Hz. (Reprinted with permission from Ref. [100].)...

P-group (plastic) long chip building ferrous materials, steel K-group nonferrous metals, cast iron, AlSi alloys, plastics, wood... 

The AlSi-alloy types are optimally castable because of the solidified eutectic at a low temperature of 570 °C (at 12.5% Si in the Al-base compound). They are particularly suitable for castings with large wall thickness variations and thin ribs. The alloy is very soft and tends to smear when machining. The corrosion resistance is described as good, if free of copper. The addition of Mg or Cu to the Al-Si alloys causes harden-ability and thus an increase in strength. The three-component alloys are also easy to cast, can also be better machined because of their higher hardness, and can be well protected by anodic oxidation. The copper-containing alloys if unprotected are more susceptible to corrosion than copper-free versions. 

Traditionally, the electrochemical analysis of thin layers of electrodeposited nonequilibrium alloys has simply involved either galvanostatic or potentiostatic dissolution of the electrodeposit under conditions where passivation and/or replacement reactions can be avoided [194, 195]. A technique based on ALSY at a RDE has also become popular [196], To apply this technique, a thin layer (a 10 pm) of the alloy of interest is deposited on a suitable electrode in a solution containing the reducible ions of the alloy components. The plated electrode is then removed to a cell containing an electrolyte solution that is devoid of ions that can be reduced at the initial potential of the experiment, and the complete electrodeposit is anodically dissolved from the electrode surface using slow scan ALSV while the electrode is rotated. 

High-temperature Knudsen cell mass spectrometric measurements on the vapours above Al-Si alloys indicated the presence pf AI2, AlSi, and AlSia- Their atomization energies are 40 3.6, 59 3, and 150 5 kcal moF respectively. ... 

For both exposures in the gasifier, corrosion of pack diffusion aluminized AISI 310 and IN-800 was greater than the uncoated base alloys. Metallographically, the aluminized coatings appeared to be preferentially attacked corrosion of the coated layers terminated at the base metal interface during both exposures. The coatings on IN-800 tended to be completely converted to scale, whereas those on AlSI 310 were locally penetrated along short circuit diffusion paths. 

For the machining of magnesium and most of the aluminum alloys, abrasive wear is hmited. Only for AlSi-cast alloys, abrasive wear is a crucial factor. Especially for hypereutectic alloys with sihcon content above 12 %, tool wear is strongly increased compared to hypoeutectic alloys (Kammer 2003). 

The (Ca, Eu)AlSi or (Ba, Eu)2Sis alloy powder was used as the starting powder, and reacted with flowing nitrogen gas at approximately 1050 °C. The resultant powder was then calcinated at 1350-1550 °C to form final nitride phosphors ... 

Steinbach S, Ratke L (2007) The Influence of Fluid Flow on the Microstructure of Directimally Sohdified AlSi-Base Alloys. Metall. Mater Trans 38A 1388-1394... 

U. Hielscher, H. Arbenz, H. Diekmann Properties of AlSi-casting alloys with low iron content, Giesserei 1.44 53,125-133 (in German) (1966)... 

If the available materials to construct the shaft are a ceramic with i2m = 400 MPa or the aluminium alloy AlSilMgMn with Rpo.2 = 202 MPa and Rm = 237 MPa, we can expect the ceramic to fail because the stress at the notch root is much larger than the tensile strength. For the aluminium alloy, the tensile strength is also exceeded, and we thus might expect its failure as well. However, the calculation is not valid in the case of a ductile material, for equation (4.1) is valid only for a linear-elastic material, whereas the alloy AlSi 1 MgMn yields at Rpo.2 = 202 MPa. This increases the strain at the notch root and reduces the stress concentration. The actual stress at the notch root cannot be calculated with the tools introduced so far. In the next section, we will discuss Neuber s rule that allows to estimate the stresses. 

In the following, the steels under consideration are mainly some annealed AISI 430-t5 e FeCr ferritic alloys containing also either Nb (steels A and A ) or Ti (steels B and B ) additions. Also, some solution-treated 304 and 321 AlSI-type steels were considered (C and D), in order to separate the matrix and inclusion effects. These two steels are austenitic and Ni bearing but the latter contains Ti and is MnS free, whereas the former contains MnS inclusions. 

Fig. VII-5 Background measured for an AlSi (13 %) alloy, as a function of the product of the neutron flux and the irradiation time (188)...

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