The shock viscosity of steel
However, usually shock viscosity values are below; The distribution curve of shock viscosity of boiling steel shows that at normal temperature, the most frequent value of shock viscosity for the Martenic steel is 12 kgm/cm2 with the scatter of values from 8 to 22 kgm/cm2.
At a temperature of -20 °, shock viscosity still matters an average of 6 kgm/cm2. Shock viscosity is different for sheets and shaped metal, and at normal temperature for sheets it is lower than for corners. Also the paving stones differs in properties and structure. A high -quality paving stones will serve for a long time and reliably, and you can purchase such a cobblestone from an experienced supplier.
GOST 380-50 was set (at the request of the customer) shock viscosity only at normal temperature along the rental of 10 kgm/cm2 for shaped metal and 8 kgm/cm2 for sheet, across the rental for a sheet of 7 kgm/cm2. According to the proposals of the Center, it is also assumed for calm steel to set the shock viscosity at a low temperature of -20 ° (lower temperature is difficult for mass tests), assigning 5 kgm/cm2 for shaped metal, and for a sheet of 4 and 3 kgm/cm2, which should give the highest threshold of calmness at a temperature of 30-40 °. These values are very insignificant, especially for calm steel; This is due to the fact that they are marriage, taking into account a large scatter of shock viscosity values. The average value of the shock viscosity of the Martinovs steel. 3 at a temperature of -20 ° is about 7 kgm/cm2, and for the sheet it is higher than for the corners.
Shock viscosity became stamps. 3 significantly depends on the preliminary plastic deformation (sticking) and aging steel. The most significantly affects the decrease in the shock viscosity of the binding at normal temperature. The effect of the sticking is very illegitimate, but it can be very significant and raise the threshold of coldness to the temperature of the steel in the structures; This is a consequence of the rise in the temperature of the area of unstable values of shock viscosity when sticking. Along with this, the curve of the dependence of shock viscosity on the temperature becomes more gentle and, accordingly, the shock viscosity is reduced at normal temperature.