Comparison of Fe based amorphous alloy with cold rolled silicon steel

      Since early 2005, due to the orientation of cold rolled silicon steel strip, imbalanced supply of and demand for domestic orientation cold-rolled silicon steel belt material price rising rapidly, now has more than the price of the iron base amorphous alloy strip. Under the condition of the market price now, iron-based amorphous alloy instead of orientation in the field of industrial frequency power transformer cold-rolled silicon steel, is no longer possible, has become a reality. In the power transformer industry, distribution transformer manufacturers have turned to core material from the orientation of cold rolled silicon steel iron base amorphous alloy. At the same time, from July 1, 2006, mandatory national standard "the allowable value of energy efficiency and energy efficiency evaluation value of the distribution transformer" formally implemented, more driven by using iron base amorphous alloy distribution transformer instead of the orientation of cold rolled silicon steel boom. Like distribution transformer, the power frequency power transformer iron base amorphous alloy cold rolled silicon steel instead of orientation, will be a power electronic transformer in a major new progress. Iron base amorphous alloy in the field of power frequency and intermediate frequency, is competing with silicon steel. Iron-based amorphous alloy compared to silicon steel, has the following advantages and disadvantages.  iron base saturation magnetic flux density of amorphous alloy Bs is lower than silicon, however, under the same Bm, the wastage of the iron base amorphous alloy is smaller than 3% of the 0.23 mm thick silicon steel. The reason of low loss are usually considered to be a iron base amorphous alloy thin strip thickness, high resistivity. This is just one aspect, the main reason is that more iron base amorphous alloy is amorphous, atomic arrangement is random, there is no atom directional row column magnetocrystalline anisotropy, there is no local deformation and the migration of grain boundary. Therefore, obstruction of domain wall movement and the magnetic moment rotational energy barrier is very small, with unprecedented soft magnetic, so high permeability, small coercive force, low loss.
Iron-based amorphous alloy core filling coefficient is 0.84 ~ 0.86, compared with the silicon steel filling coefficient is 0.90 ~ 0.95, the same weight of iron base amorphous alloy core volume is bigger than silicon steel core. iron-based amorphous alloy core work of magnetic flux density of 1.35 T - 1.35 T, silicon steel of 1.6 T ~ 1.7 T. Iron-based amorphous alloy is the weight of the power frequency transformer silicon steel about 130% of the weight of the power frequency transformer. However, even if the weight is heavy, for the same capacity of power frequency transformer, magnetic core adopts the wastage of the iron base amorphous alloy, 70% ~ 80% lower than using silicon steel.

      Assuming power frequency transformer load loss (copper loss) are all the same, load rate is 50%. So, to make the silicon steel power frequency transformer iron loss and the iron base amorphous alloy transformer, power frequency, silicon steel is the weight of the iron base amorphous alloy transformer 184 times. As a result, the domestic some identity aside transformer loss level, generally talking about the weight of the iron base amorphous alloy transformer power frequency, cost and price, power frequency transformer silicon steel is 130% ~ 150%, does not conform to the requirements of the market price performance ratio of the original. Abroad put forward two methods of comparison, one is under the condition of depletion of the same, and the two kinds of power frequency transformer used in copper, iron materials, weight and price comparison. Another method is to iron base amorphous alloy power frequency transformer loss lower wattage, converted into money to compensate. No-load loss converted into 5 ~ 11 dollars per watt, equal to 42 ~ 92 yuan. Per watt converted into load loss $0.7 ~ 1.0, the equivalent of 6 ~ 8.3 yuan. For example a 50 hz, 5 kva single-phase transformer silicon steel core, quotation is RMB 1700 / sets; 28 W, no-load loss at 60 yuan/W, is 1680 yuan. Negative load losses of 110 W, at 8 yuan/W, is 880 yuan. Then, the overall evaluating price is RMB 4260 / sets. With iron-based amorphous alloy core, price is RMB 2500 / sets; No-load loss 6 w, into renminbi 360 yuan. 110 w, load loss into renminbi 880 yuan, the overall evaluating price is RMB 3740 / sets. If not considering loss, offer single calculation, 5 kva iron-based amorphous alloy transformer power frequency for 147% of the power frequency transformer silicon steel. If you consider loss, overall evaluating price of 89%.

      Now test the power frequency power transformer magnetic core material loss, is the distortion is less than 2% of the sine voltage. While the actual power grid power frequency distortion is 5%. In this case, the loss of iron base amorphous alloy increased to 106%, the loss of silicon steel up to 123%. If the higher harmonic is large, the distortion of 75% (such as power frequency rectifier transformer), under the condition of iron base amorphous alloy loss increases to 160%, increased to more than 300% loss of silicon steel. That iron base amorphous alloy power waveform distortion resistance is better than silicon.  iron-based amorphous alloy magnetostrictive coefficient is big, 3 ~ 5 times that of silicon steel.

       Therefore, iron base amorphous alloy transformer noise sound power frequency is 120% of the silicon steel power frequency transformer noise, bigger 3 ~ 5 db.  the current market, iron-based amorphous alloy strip is 0.23 mm price 3% 150% of the oriented silicon steel, 3% is 0.15 mm of oriented silicon steel (through special processing) is about 40%.

      Iron-based amorphous alloy annealing temperature is lower than silicon steel, small energy consumption, and iron-based amorphous alloy core generally manufactured by special factory. Silicon steel core transformer factory made in general.  iron-based amorphous alloy strips of iron 78% 81%, 13.5% boron, containing silicon 3.5% 8%, also contains trace amounts of nickel and cobalt and other metallic elements. From the cost structure analysis, and cost of making steel. But because the technology is still not perfect, amorphous alloy strip yield under low has become a important reason for the high cost. But along with the technical progress, yield increase, amorphous alloy strip production cost is expected to decline year by year.

      According to the above comparison, as long as reached a certain scale of production, iron-based amorphous alloys in the frequency range of electronic transformer will replace part of the silicon steel market. In 400 hz to 10 KHZ frequency range, even with a new type of silicon steel, iron-based amorphous alloys will replace most of the 0.15 mm below the thickness of the silicon steel market.