No abstract

Normalizing of hot rolled bands results in better magnetic properties (lower iron loss and higher flux density) than non-normalizing, which is caused by the fact that normalized steels show larger final grain size, higher volume faction of cube texture, and lower volume fraction of y fiber than non-normalized ones. Antimony and tin alloyed steels provide the best magnetic properties among the test steels and have bigger grain size than boron steel. The first group also has a higher fraction of (100)-fiber and a lower share of y fiber than the boron steel. However, the effects of these elements on textures with or without normalizing are minimal. The texture factor (TF) has a stong influence on the magnetic properties of normalized NO steels, while the magnetic properties improve with a decrease in TF, but this effect is not so pronounced for non-normalized materials.

Sound speed and attenuation in sandy sediments are important acoustic parameters. But the uncertainties of current in-situ measurements at low-frequency are very large and the data are not sufficient to be used to test theory predictions. As an alternative, measurements in a water filled isolated reverberation chamber were attempted in laboratory, which preserves lower frequency limitation and smaller scale requirement of water tank. In order to know the feasibility of the method, a type of fine sand sediments was measured. Spatial averaged reflection and transmission coefficients of the sand layer and attenuation were calculated over the frequency range of 90–170 kHz. And sound speed was inverted with these measured parameters. After then measurements at low-frequency till to 2 kHz were tried in the same tank.