Ultra pure ferritic stainless steel is a kind of new stainless steel grade with high quality developed in the mid-twentieth century,it is characterized by ultra low Carbon and Nitrogen content and micro-alloying with ...Ultra pure ferritic stainless steel is a kind of new stainless steel grade with high quality developed in the mid-twentieth century,it is characterized by ultra low Carbon and Nitrogen content and micro-alloying with Ti, Nb,V,Cu etc.,so it overcomes a lot of use shortcomings of the ordinary ferritic stainless steel,such as intergranular corrosion sensitivity,low ductility and toughness under atmosphere temperature,crack inclining at the weld zone etc.,namely,it has better performance than the ordinary ferritic stainless steel in the aspect of corrosion resistance,toughness and weldability etc.Furthermore,a series of secondary refining equipments and technologies have been invented from the 1960s,low or ultra low Carbon and Nitrogen content in the molten stainless steel can be obtained during manufacturing production.Therefore,such steel has been applied in many fields,leading to the very rapid development over the past half century. This paper focuses on the secondary refining process which is the most important step of the whole steel-making process for the ultra pure ferritic stainless.Firstly,some difficulties of the secondary refining process are described,including the high purification in terms of both Carbon and Nitrogen contents,high efficient and stable control.Secondly,the development and progress of the secondary refining technology for ultra pure ferritic stainless is introduced in terms of the refining equipments,metallurgical process and assistant technologies.Some most famous secondary refining equipments and metallurgical technologies for ultra pure ferritic stainless steel had been invented mainly by Japan and European companies from 1960s to 1990s,such as VOD,SS-VOD,AOD-VCR, VOD-PB etc..During the same time of wide application of these secondary refining equipments and technologies,in order to strengthen the function and capacity of these refining equipments,some advanced assistant technologies were also introduced and applied,which consists of top lance,special raw materials,ladle refractory,process monitoring and mathematic model and so on.Finally,the prospect in the future was made for the development of secondary refining process for ultra pure ferritic stainless in terms of high efficiency,ultra purification,stable control with process model etc.展开更多
文摘Ultra pure ferritic stainless steel is a kind of new stainless steel grade with high quality developed in the mid-twentieth century,it is characterized by ultra low Carbon and Nitrogen content and micro-alloying with Ti, Nb,V,Cu etc.,so it overcomes a lot of use shortcomings of the ordinary ferritic stainless steel,such as intergranular corrosion sensitivity,low ductility and toughness under atmosphere temperature,crack inclining at the weld zone etc.,namely,it has better performance than the ordinary ferritic stainless steel in the aspect of corrosion resistance,toughness and weldability etc.Furthermore,a series of secondary refining equipments and technologies have been invented from the 1960s,low or ultra low Carbon and Nitrogen content in the molten stainless steel can be obtained during manufacturing production.Therefore,such steel has been applied in many fields,leading to the very rapid development over the past half century. This paper focuses on the secondary refining process which is the most important step of the whole steel-making process for the ultra pure ferritic stainless.Firstly,some difficulties of the secondary refining process are described,including the high purification in terms of both Carbon and Nitrogen contents,high efficient and stable control.Secondly,the development and progress of the secondary refining technology for ultra pure ferritic stainless is introduced in terms of the refining equipments,metallurgical process and assistant technologies.Some most famous secondary refining equipments and metallurgical technologies for ultra pure ferritic stainless steel had been invented mainly by Japan and European companies from 1960s to 1990s,such as VOD,SS-VOD,AOD-VCR, VOD-PB etc..During the same time of wide application of these secondary refining equipments and technologies,in order to strengthen the function and capacity of these refining equipments,some advanced assistant technologies were also introduced and applied,which consists of top lance,special raw materials,ladle refractory,process monitoring and mathematic model and so on.Finally,the prospect in the future was made for the development of secondary refining process for ultra pure ferritic stainless in terms of high efficiency,ultra purification,stable control with process model etc.
