Title of Invention | A PROCESS FOR THE PRODUCTION OF FERROUS BASED COMPOSITE MATERIALS . |
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Abstract | This invention relates to a process for the preparation of TiC reinceforced ferrous based composite materials from industrial waste. |
Full Text | FIELD OF THE INVENTION This invention relates to s process for the production of ferrous based composite materials. This invention further relates to a process for the preparation of TiC reinforced ferrous based composite materials from industrial waste. The need for long—lasting component has led to the development of wear resistant materials. Iron matrix composites have gained attention essentially as potential wear resistant materials. As engineering materials, iron and steel are yet to be displaced from the top slot by the range of polymers/ceramics and other metals in terms of volume of consumption because of their versa- tility and low cost. Achievement of the improved wear resistance by ceramic particle reinforcement is possible and has been proved. However, it is the economy of producing the composite that will decide whether it would be able to compete with the wide range of steels/alloy steels/alloy irons already available in the market. As there is a constant search for novel and econo- mical synthesis routes, the various routes of synthesis of Fe- Tic composite has been evolving over the years gradually. Several processes are available for the synthesis of these kind of TiC reinforced ferrous based composites, namely powder metallurgy technique, carbothermic reduction of ilmenite or rutile in presence of iron. Most of the iron-based composites are produced by powder metal- lurgical route and reinforced with TiC. This product is marketed under the trade name FERROTIC, TIC ALLOY, FERROTITANIT. The correlation between microstructure and mechanical properties of TiC reinforced white iron matrix; composites and hot work tool steel matrix composites produced by hot isostatic pressing has been studied. Further, a microstructure development and sintering kinetics of high-speed steel based composites re-informed with either TiC or NbC and ball milling assisted low temperature formation of Fe—TiC composite from ilmenite-csrbon mixture have also been studied. The production of composite via powder metallurgy route has its limitations, eg. mixing of matrix powder and reinforcing particle must be through in order to achieve uniform dispersion of rein- forcing phase. Sintering cycle and environment must be chosen critically to obtain components with near theoretical density, difficulty af machining or trimming sintered parts because of high hardness of the materials. One then looks to the other common route, eg.casting route. Ceramic particles in metals and alloy were assumed as undesirable inclusion in past. In the mid-sixties, nickel coated graphite powders were incorporated in aluminum alloys by injecting the powders together with argon gas into a molten bath of the alloy and this marked the beginning of cast metal -- matrix particulate composites (MMPC). This was followed by specific techniques to generate cast composites.. The dispersion of TiC in liquid iron alloy was studied and a qualitative assessment of the condition of dispersion was established. Terry et al have also tried to develop in—situ Fe — TiC composite by reaction in liquid iron alloys. In an attempt to develop Fe-TiC reinforced cast composites through a novel rout; Galgali et al worked extensively on the production and charac- terisation of TiC reinforced Fe based composite. The TiC rein- forced iron based composites were produced by direct carbothermic reduction of ilmenite ore in a bed of steel scrap contained in a plasma reactor. Galgali has also produced TiC reinforced steel- based composite. The TiC reinforced iron based composites cere produced by direct carbothermic reduction of illmenite ore in a bed of steel scrap contained in a plasma reactor. Galgali has also produced TiC reinforced steel—based composites by dissolving Fe-TiC rich master alloy in liquid steel. This approach was followed since carbothermic reduction of ilmenite in a graphite crucible does not permit the preparation of TiC reinforced steel of based composites by a single smelting operation due to the inevitable pick up of carbon. However, difficulty arises due to loss of Ti by oxidation before incorporation into the melt. However, the need exists to provide more economical synthefi- routes involving high energy efficiency and low cost oron production. OBJECTS OF THE INVENTION It is therefore en object of this invention to propose a process for the production of ferrous based composite materials from industrial wastes which involves in-situ generation of titanium carbide particles. It is a further object of this invention to propose a process for the production of ferrous based composite materials from indus- trial wastes which is simple, energy efficient and is therefore economic a 1 . BRIEF DESCRIPTION OF THE INVENTION Thus according to this invention is provided a process for the preparation of ferrous based composite comprising subjecting industrial waste material to the step of alumino thermic reduc- tion in the presence of cabron. In accordance with this invention, the charge needed to synthe- size the composite consists of siliceous sand, aluminum powder (stoichiometric amount) and C in the form of cast iron and/or graphite. The charge is preheated in a pit furnace in a clay graphite crucible. The crucibles are coated with zircon paint to prevent carbon pick up. The crucible is removed out of the furnace when requisite temperature is reached and then the reac- tion is triggered by adding magnesium turnings. The heat gene- rated due to aluminothermic reaction is high enough to melt the charge completely and uniformly. A bottom pouring arrangement is made so that the liquid metal can be poured directly into a mould by opening the plug at the bottom of the crucible. Siliceous sand which is a waste product of the aluminium extrac- tion plant is a source of Fe2o3 and TiO2. A typical sand composition comprises, for example, 73.1'/.Fe2o3 , 6.26'/. Al2o3 , 3.63X TiO2 , 2.5'A Na2O and 3.84% SiO2 by weight with other impurities, like NiO, Cr2 O3 and V2 O5 to make up the balance. The sand is rich in Fe2O3 and also contains a substantial amount of TiO2 . A typical micrograph of the cast composite is shown in Fig.l of the accompanying drawings. Composites produced by this method show impressive wear resis- tance and thus can find application as wear resistance materials. The wear resistance property of the composite is better than some commercially available tool steels and it has the potential as ambient temperature tool material. This is depicted in Fig.2 which shows the cumulative weight loss in wear of as cast compo- sites of varying carbon content in steel matrix (designated as (a>, (b) and are : (a) Abrasive medium -220 grit SiC paper; (b) Normal load -10.90N; -1 (c) Sliding speed-1.25 ms The hardness data of as cast composites is shown in T«ble I, where materials (a), (b) and (C) are composites of varying carbon content in steel matrix. The main advantage of producing Fe based composite via alumino- thermic reduction is the simplicity of the method by which the composite can be produced. The heat evolved during aluminothermic: reduction will melt the charge. Therefore, no expensive experi- mental set up but only some cheap raw materials are needed to synthesize the composite- As a result, even a small scale foundry can produce Fe based composite with improvement in properties over conventional steel/cast iron castings. The Fi-TiC composite made via aluminothermic reduction of sili- ceous sand in presence of carbon has shown very good wear resis- tance properties. The present study assumes greater significance in the light of the fact that 'discard' by product is the main raw material. The composite produced via this method has the potential of replacing some of the expensive tool materials. The statement is justified not only due to the properties they exhibit but also owing to the ease of synthesis and the economy of the process. We Claim 1. A process for the preparation of ferrous based composite comprising preheating the industrial waste material such as herein described to a temperature of upto 900° C to form a heated charge mixture and subjecting it to the step of alumino thermic reduction by adding magnesium turnings in the presence of carbon. 2. The process as claimed in claim I, wherein said industrial waste comprises mainly siliceous sand consisting of oxides of iron, aluminium, titanium, sodium and silicon with impurities such as oxides of nickel, chromium and vanadium. 3. The process as claimed in claim I, wherein the carbon is in a form selected from cast iron, graphite, singly or in combination. 4. The process as claimed in claim I, wherein the charge mixture after the alumino thermic reduction, is poured in the liquid form into moulds for the preparation of composites. 5. A process for the preparation of ferrous based composite substantially as herein described and illustrated. Dated this 12th day of March, 2002 (I. BANERJEE) of L. S. DAVAR & CO Applicants' Agent This invention relates to a process for the preparation of TiC reinceforced ferrous based composite materials from industrial waste. |
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143-cal-2001-granted-abstract.pdf
143-cal-2001-granted-claims.pdf
143-cal-2001-granted-correspondence.pdf
143-cal-2001-granted-description (complete).pdf
143-cal-2001-granted-form 1.pdf
143-cal-2001-granted-form 18.pdf
143-cal-2001-granted-form 2.pdf
143-cal-2001-granted-form 3.pdf
143-cal-2001-granted-form 5.pdf
143-cal-2001-granted-reply to examination report.pdf
143-cal-2001-granted-specification.pdf
Patent Number | 233871 | |||||||||
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Indian Patent Application Number | 143/CAL/2001 | |||||||||
PG Journal Number | 16/2009 | |||||||||
Publication Date | 17-Apr-2009 | |||||||||
Grant Date | 16-Apr-2009 | |||||||||
Date of Filing | 13-Mar-2001 | |||||||||
Name of Patentee | INDIAN INSTITUTE OF TECHNOLOGY | |||||||||
Applicant Address | INSTITUTE OF KHARAGPUR | |||||||||
Inventors:
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PCT International Classification Number | C22C 38/00 | |||||||||
PCT International Application Number | N/A | |||||||||
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PCT Conventions:
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