Cast & Sintered AlNiCo Magnets 20150205
AlNiCo Permanent Magnet Manufacturer – China Rare Earth Magnet Limited
Cast alnico magnets are made by casting techniques.
The technique is quite simple which was widely used during World WarⅡ. Through smelting furnace, metal materials smelt into liquid which blends and alloys in sand moulds. After certain rough machining and heat processing, the materials gains magnetic performances and finished products are produced after refining process. Cast alnico permanent magnets are fit for manufacturing with complicated or large sizes. But tolerance is big, which always needs post-process. Due to the term of alloying, its relative density is bigger that sintered alnico rare earth magnets, so its magnetic performance is better than sintered one. During production process, as long as you pay attention to design of sand moulds, you can produce complicated shapes. But this is limited by molding precision of cast alnico magnets and complicated shapes are hard to control. That’s because during cooling process, some transformation may happen.
Composition of cast alnico is similar to that of sintered alnico. A technique called columnar crystal cannot be matched by sintering techniques. Columnar crystal refers to grain’s structure that is formed by controlling its cooling direction and speed and this structure can obviously improve performance of cast permanent magnet.
Sintered alnico magnets are made by powder metallurgy.
There are many introductions about alnico magnet in Baidu and Wikipedia. We can roughly know that alnico is made of Al, Ni, Co, Cu, Ti, Fe and Nb. Absolutely, not all classes of alnico contains these elements. Such as alnico alloy which is free from Co. Generally speaking, alnico magnetic steels are a series of alloy. In fact, they are iron-base alloy made of Al and Ni.
Sintered alnico is formed by metal powder mixture. With a press machine controlling size of blanks, it is sintered in vacuum or air sintering furnace. After alloying, it is processed by heat, in which way it can obtain magnetic performance. The shapes are simple, because powder press machines are not suitable for complicated shapes. In addition, before refining process, requirement of tolerance of dimension is high. These features enable alnico to be applied to some magnetic parts that needs high precision.
Performance of sintered alnico is relatively high, but it is weaker that casting alnico. Its biggest characteristic is the stable performance and temperature co-efficient can reach -0.01% /C~-0.02%/C, which is excellent heat-resistant rare earth permanent magnetic materials . It is widely applied to ammeters, motors, magnetic sensors, instruments, relays and some magnetic parts that require heat resistance and high precision.
Cast alnico magnets are made by casting techniques.
The technique is quite simple which was widely used during World WarⅡ. Through smelting furnace, metal materials smelt into liquid which blends and alloys in sand moulds. After certain rough machining and heat processing, the materials gains magnetic performances and finished products are produced after refining process. Cast alnico permanent magnets are fit for manufacturing with complicated or large sizes. But tolerance is big, which always needs post-process. Due to the term of alloying, its relative density is bigger that sintered alnico rare earth magnets, so its magnetic performance is better than sintered one. During production process, as long as you pay attention to design of sand moulds, you can produce complicated shapes. But this is limited by molding precision of cast alnico magnets and complicated shapes are hard to control. That’s because during cooling process, some transformation may happen.
Composition of cast alnico is similar to that of sintered alnico. A technique called columnar crystal cannot be matched by sintering techniques. Columnar crystal refers to grain’s structure that is formed by controlling its cooling direction and speed and this structure can obviously improve performance of cast permanent magnet.
Sintered alnico magnets are made by powder metallurgy.
There are many introductions about alnico magnet in Baidu and Wikipedia. We can roughly know that alnico is made of Al, Ni, Co, Cu, Ti, Fe and Nb. Absolutely, not all classes of alnico contains these elements. Such as alnico alloy which is free from Co. Generally speaking, alnico magnetic steels are a series of alloy. In fact, they are iron-base alloy made of Al and Ni.
Sintered alnico is formed by metal powder mixture. With a press machine controlling size of blanks, it is sintered in vacuum or air sintering furnace. After alloying, it is processed by heat, in which way it can obtain magnetic performance. The shapes are simple, because powder press machines are not suitable for complicated shapes. In addition, before refining process, requirement of tolerance of dimension is high. These features enable alnico to be applied to some magnetic parts that needs high precision.
Performance of sintered alnico is relatively high, but it is weaker that casting alnico. Its biggest characteristic is the stable performance and temperature co-efficient can reach -0.01% /C~-0.02%/C, which is excellent heat-resistant rare earth permanent magnetic materials . It is widely applied to ammeters, motors, magnetic sensors, instruments, relays and some magnetic parts that require heat resistance and high precision.
