Cobalt in Steels

Cobalt in Steels  Cobalt (Co) (atomic number 27 and atomic weight 58.94) has density of 8.85 gm/cc. Melting point of Co is 1493 deg C and boiling point is 3100 deg C. At temperatures below 417 deg C cobalt exhibits a hexagonal close packed structure. Between 417  deg C and its melting point of 1493 deg C, Co has a face centered cubic (fcc) structure. Co is a magnetic metal with a curie temperature of 1121 deg C. The phase diagram of the Fe-Co binary system and is given at Fig 1. Fig 1 Fe-Co binary phase diagram Co is not a popular element which is commonly added to alloy steels. It does have some effects but these can also be achieved with other alloying elements such as molybdenum (Mo), and nickel (Ni) etc. at lower costs and mostly with better results. Due to this factor, Co does not find enough use in high tonnage low alloy steel production. However it does have some niche markets in steel. Co becomes highly radioactive when exposed to the intense radiation of nuclear reactors, and as a result, any stainless steel that is in nuclear service will have a restriction in the Co content which is  usually around 0.2 % maximum. Adding agents In the production of co bearing alloy steels, additions of Co during the steel making is made in the form of Co metal which is supplied to steel producers in the form of briquettes, granules, and broken electrolytic cathodes. Content of Co in these additive agents is usually in the range of 98 % to 99.9 %. Scrap of super alloys normally contains high percentage of Ni and hence is not used for the production of tool steels. However this scrap can be used...

Business Process Re-engineering...

Business Process Re-engineering  Business process re-engineering (BPR) is a strategy of the management of an organization which focuses on the analysis and design of various business processes and flow of work within the organization. It seeks to help the organization radically to restructure its operations by focusing on the ground up design of the business processes. BPR helps the organization to rethink in fundamental way how it should do the work in order to drastically reduce operational costs, improve service to its customers, and become a world class organization.  It is also sometimes known as business process redesign, business transformation, or business process change management. BPR as an approach to radical organizational change is a relatively recent concept emerging from the two papers written by Davenport and Short (1990), and Hammer (1990). These papers gave rise to two popular books in 1993 written by (i) by Davenport , and (ii) by Hammer and Champy. The authors of these books promoted the idea that sometimes radical redesign and reorganization of the organization becomes necessary for lowering the costs and increasing the quality of service. The concept of BPR has become popular in a short period of time, promising amazing results very quickly in relation to corporate and technological change, transformation and competitive pressures. BPR strategy presumes that the business processes are set of logically related tasks performed to achieve defined business outcomes. Re-engineering of these processes emphasize a holistic focus on business objectives, and processes related to them are recreated totally rather than carrying out the optimization of the sub processes. The most notable definitions of BPR are given below. Hammer and Champy has defined BPR as ‘… the fundamental rethinking and radical redesign of business processes to achieve dramatic improvements in critical contemporary modern measures of performance, such as...

Iron Ore Pellets and Pelletization Process Nov26

Iron Ore Pellets and Pelletization Process...

Iron Ore Pellets and Pelletization Process Pelletizing of iron ore was started in the 1950s to facilitate the utilization of finely ground iron ore concentrates in steel production. For the pelletizing of iron ore there are two main types of processes namely, the straight travelling grate (STG) process and the grate kiln (GK) process. In the STG process, a stationary bed of pellets is transported on an endless travelling grate through the drying, oxidation, sintering and cooling zones. In the GK process, drying and most of the oxidation is accomplished in a stationary pellet bed transported on a travelling grate. Thereafter, the pellets are loaded in a rotary kiln for sintering and then on a circular cooler for cooling. The pelletizing processes are discussed in the article under the link http://ispatguru.com/iron-ore-pellets-and-pelletizing-processes/. The pellets may be acid or fluxed pellets. Acid pellets – Basicity of acid pellets is usually less than 0.1. The fired pellet strength is, to a certain degree, due to hematite bridges of polycrystalline structure. These pellets normally have large volume of open pores. The reduction gas quickly penetrates through these pores into the pellet core and simultaneously attacks the structure in many places. This results into an early structural change which begins at low temperatures over the entire pellet volume. Fluxed pellets – These are also known as basic pellets. Basicity of fluxed pellets is greater than 0.1 and can vary. Basicity of normal basic pellets range from 0.1 to 0.6 and have low CaO percentage. During the firing of these pellets, a glassy slag phase consisting of SiO2, CaO, and Fe2O3 of varying percentage is formed. Due to increased flux addition, there is formation of some slag and due to it, there is to a certain extent slag bonding with...

Boron in Steels

Boron in Steels  Boron (B) (atomic number 5 and atomic weight 10.81) has density of 2.34 gm/cc. Melting point of B is 2076 deg C and boiling point is 3927 deg C. B is a solid material at the atmospheric pressure and at 0 deg C temperature. The phase diagram of the Fe-B binary system and equilibrium phase diagram at low concentrations of B  is given at Fig 1. Fig 1 Fe-B phase diagram and equilibrium phase diagram at low B concentrations  B steels are becoming increasingly popular and their application is becoming more diverse. Their high properties, at a reasonable price, are achieved through advanced manufacturing technology. Although B steels were originally designed mainly for the hard, wear resistant elements, now they are also being used for a wider application. B is useful as an alloying element in the steel because of its effect on hardenability enhancement. It is added to carbon (C) and low alloyed steels at concentration levels of 0.0015 % to 0.0030 % for increasing the hardness level through the enhancement of hardenability. B reacts readily with oxygen (O) and nitrogen (N) and is not useful to steels if it is in  combined form. Hence care is to be taken during steelmaking to ensure that B is adequately protected. If this precaution is not taken then it can lead to erratic heat treatment response. Addition agents B is used in steelmakers as ferro-boron (Fe-B) which is a low cost addition agent. Fe-B comes in several grades. High C Fe-B contains up to 2 % C and normally comes in three grades containing (i) 10 %- 15 % B, (ii) 15 % – 20 % B, and (iii) over 20 % B. Low  C Fe-B contains less than 0.5 % C...

Balanced Scorecard

Balanced Scorecard  Balanced scorecard (BSC) is a strategic planning and management tool which is extensively used by the organizations  worldwide to align business activities to the vision and strategy of the organization, improve internal and external communications, and monitor organization performance against strategic goals. The concept was originated in 1992 by Robert Kaplan and David Norton as a performance measurement framework that added strategic non-financial performance measures to traditional financial metrics for providing management of the organization a balanced view of the organizational performance. Kaplan and Norton have described the BSC as given below. “The balanced scorecard retains traditional financial measures. But financial measures tell the story of past events, an adequate story for industrial age companies for which investments in long-term capabilities and customer relationships were not critical for success. These financial measures are inadequate, however, for guiding and evaluating the journey that information age companies must make to create future value through investment in customers, suppliers, employees, processes, technology, and innovation.” In the view of Kaplan and Norton the measurement is fundamental to the organizational management. If the organization is to improve the management of its intangible assets then it has to integrate the measurement of the intangible assets into the management system. The concept explain that if the managers can measure what they say and express it in numbers then they know something about it. But if they cannot measure it and cannot express in numbers then their knowledge of the subject is very limited and unsatisfactory. The concept is based on principle that the things cannot be improved unless they are measured. Though the ‘balanced scorecard’ phrase received its popularity in 1992, but this type of approach was followed even earlier by many organizations. Several organizations have used systems consisting...