Потребителски вход

Запомни ме | Регистрация
Постинг
23.06.2010 09:53 - Доклади на д-р инж. Богомил Великов Колев, публикувани в Турция в сборник от международен конгрес в-Истанбул 2002
Автор: bogomil Категория: Технологии   
Прочетен: 1377 Коментари: 0 Гласове:
0



ON SOME PROBLEMS OF HEAT TREATMENT AND STRUCTURE FORMATION OF NOVEL ALLOYS DESIGNED FOR GENERAL AND SPECIALISED MACHINE BUILDING Dr.Eng.Bogomil Velikov Kolev- Institute of Metal Science(IMS), Bulgarian Academy of Sciences(BAS) 67 ”Shipchensky prohod’’ str., 1574 Sofia, Bulgaria The paper presents in general framework a part of by now obtained results of the authors works in the period 1974-2001 about possibilities for obtaining new high-strength and wear-resistant cast alloys on Fe-C basis - complex alloyed steels and cast iron of different systems with differentstructure. Bulgarian methods with gas counter pressure (MOMGP) presents a fundamental innovation for great potential possibilities to develop and solve actual- priority Global problems of Mankind; creation of technologic and ecological as well as economically profitable machines and devices, new materials (alloys) and their products. One of the most perspective directions of MOMGP is creation of new machine-building materials(steels and cast iron), alloyed with gaseous (volatile) elements - Nitrogen and others. Of all known methods for improvement of structure and properties of the alloys on Ferro-basis the most effective is alloying. MOMGP outlined the principal fundamental possibilities and directions for development of the new gaseous metallurgy with volatile elements and substances. Nitrogen as the most common in Nature gas and residual product of a number of industrial production, processing the unique property to substitute expensive and deficit elements like: Ni, Cu,Co, (Mn) etc. and to improve some physic-mechanical and exploitation characteristics in times, not in percentage, completely corres- ponds to some of the challenges and the outlined Global problems of Mankind for the present and future, For unexplainable reasons the efforts of scientists are concentrated mainly on the production N alloying steels for deformation. Up to now investigations in the IMS-BAS based on the unique possibilities of the methods(MOMGP) for producing non deformable alloys (cast alloys for foundry) are considerably greater. The general results are presents of the investigations on structure formation of some high strength and wearresistant complex alloyed alloys of different systems on Fe-C bases after solidification in sand moulds and after austenitization and quenching, followed by heating and cooling(ageing) within the range of 300-500-1000oC .The paper includes summary of generalised theoretical and practical results from the next problems: 1.Effects of pressure and N on structure formation of Fe-C based cast alloys-theoretical and experimental results. 2. Summary of some investigation results on the structure formation :2.1. Austenite cast alloys in Fe-Cr-Mn-C-N and Fe-Cr-Mn-C systems. The structure have been examined after casting, austenitization and quenching. In general the structure may be evaluated as solid phase reaction. 2.Alloys of the Fe-Cr-C-N system. 2.3. Complex alloyed cast alloys in other metal systems. 2.4.Thermal stability of austenite quenched cast alloys of the Fe-Cr-Mn-C-N, Fe-Cr-Mn-C, Fe-Mn-Cr-C-N, Fe-Mn-Cr-C, Fe-Mn-C-N and Fe-Mn-C (Fe-Mn-N), Fe-Cr-C-N systems An attempt to be developed the principal processes of thermal stability under heating and cooling of austenitized and quenched Ni free austenite alloys. The work presents summary of theoretical and experimental results on the ageing of this alloys. 3.Somme importance properties (physic-mechanical, wear resistance, hardenabi lity, etc). General results. 4.Industrial testing and application fields 7.Development, perspectives and prognostication on production of new complex alloyed cast alloys. The intensive progress of world science imposes the necessity to create new materials and alloys with high physico-mechanicdl and exploitation characteristics with simultaneous decrease in material energy and other expenses for achieving high quality. Development of machine building as a strategic sector is inevitably connected to the creation of ever newer and more effective technologic and ecological proces- ses in foundry. At the end of the 20-Th. and the beginning of 21-St century tradition metallurgic and foun- ding technologies are exhausted in their possibilities to solve these complex issues. From the three ther- mo dynamic factors (composition, temperature and pressure), characterising and defining processes and phenomena in substances (the Nature),and properties of materials (alloys) in classic technologies are practically used only the first two. If studying and applying of the possibilities of vacuum technologies are developed well enough vacuum technologies, then the study and application of the possibilities of pressure, still at an initial stage seems to be very perspective, having in mind the challenges of the 21-St century.
HEAT TREATMENT AND SUGGESTIONS FOR APPLICATION OF NEW COMPLEX ALLOYED CAST ALLOYS OF THE Fe-Cr-C-(N) SYSTEM Dr.Eng.Bogomil Velikov Kolev- Institute of Metal Science(IMS), Bulgarian Academy of Sciences(BAS) 67 ”Shipchensky prohod’’ str., 1574 Sofia, Bulgaria The better part of details in industrial condition work not only under abrasive, hydroabrasive, corrosion mechanic wearing, but also under complex dynamic wear. That’s why the study of mechanic characteristics of these alloys aiming to search possibilities for their improvement as well as to chose the appropriate composition is very important for the quality and efficiency of the alloys. This is connected with the solving some topical problems: lightening of machines and apparatuses decreasing the need of about, resources and energy, which become less on the earth Global ecology. The mechanic characteristics of Cr alloyed casting alloys depend on many factors of which very significant are: chemical composition, crystallisation and thermal treatment conditions. These factors determine the character of the carbide (K) and nitride (N) and carbonitride (KN) phases and the basic metal matrix. The pressure, resp. the absorbed under its influence. N sharply refine structure along with the increase of cooling rate. The information about mechanic characteristics of casting alloys of Fe-Cr-C system connected with influence of chemical composition and thermal treatment is very scarce and for casting alloys of Fe-Cr-C-N system there are no data. One of the basic problems is that high C casting alloys of that system N free are difficulty to treating cutting instruments. The long years of observation show that N improves mashinability and sharply decreases the affinity towards crashes and slots, since under crystallisationN-phases are formed which have bigger hardness, than K and take stresses easily from phase transitions. We suppose that in cutting N phases have an lubricant role very much like graphite. In patents RB25568; 26110 49451 there is a concrete worked-out regime which allows cutting wearing, making aperture, etc. These alloys aren’t used in practices without thermal treatment. On importance for it are 3 factors: austeitization, duration, situation of critic points and ToC of quenching. First factor depends an alloying degree with elements making solid solutions for replacement. N doesn’t influence. The rest factor dependable on N. The paper includes summarised results: 1. There are results presented of the research on influence on basic components (Cr, C, N) on mechanic characteristics of alloyed and heat treated wear-resistant complex alloys of the Fe-Cr-C-(N) system: Rockwell’s hardness, strength tensile(sB), strength bending (sbend.) and impact strength (ak). The regularities drawn during testing enable the right choice of a proper chemical composition for specific casts according to specific working conditions: the type of wearing and pressure. 2.Hardness (HRC) and impact strength (auk) are the most important mechanic characteristics which determine the application of complex alloyed alloys of the Fe-Cr-C and Fe-Cr-C-N systems. There have bee presented some graphic about the influence of temperature (ToC) during quenching and tempering on (HRC) and (ak) of some typical casting complex alloyed, wear resistant alloys of the Fe-Cr-C-N system. An opposite influence of the ToC during quenching on the variation of HRC and has been determined.. This necessitates a choice of HRC and ak according to working conditions in production, esp. to pressure. 3.Hardenability is an important requirement particularly for thick wall casting under abrasive, hydroabrasive, impact abrasive and corrosion mechanic wear. On the basis of the author’s methods, equipment and installation for haredenability testing of the high hardening alloys the experimental results obtained comprise a wide rage of wear resistant complex alloyed alloys of the Fe-Cr-C-(N) system, summarised in several generalised graphical dependencies. 4.The basic exploitation means of complex alloyed cast alloys of the systems Fe-Cr-C and Fe-Cr-C- with and without additional alloying is wear resistanc. During last round 15 years data show cast iron of system Fe-Cr-C (without N) are said to be alternative of wearresistance materials for working in abrasion conditions. Data for their phisicomechanic and exploitation characteristics are rare expecially by observation. There are no data for wear resistance complex alloyed cast alloys of system Fe-Cr-C-N, as well as influence of basic components on it. Result of laboratory study are confirmed by tests in industrial conditions on concrete casts. NEW HIGH STRENGTH AND WEAR RESISTANT N- DOPED AUSTENITIC STEELS AND CAST IRONS Dr.Eng.Bogomil Velikov Kolev- Institute of Metal Science(IMS), Bulgarian Academy of Sciences(BAS) 67 ”Shipchensky prohod’’ str., 1574 Sofia, Bulgaria A problem of high interest in the present development of engineering is the production of cast alloys of the austenite class that have higher values of the relative yield strength (s02). The value of s02 of classical austenite cast steels of the Hatfield type C110Mn13 are law (up to 35-40.107Pa). The value of s02 in the classical Cr-Ni austenite cast alloys type Cr18Ni9Ti are lawyer. Of all methods for strengthening (marten site transformation, cold deformation, explosive strengthening, thermomechanical and thermociclic treat ment, ageing, intermetal strengthening, etc.) the most efficient one is alloying..C and N can be used not only as substitutes for expensive and deficient elements (Co,Ni,Mn,Cu,Zn etc.) as well as austeitisators and stabilisators of the g-solid solution, but also as elements increasing mechanical characteristics. In other works on the same subject usually present results of studies on mechanical characteristics after deformation of stainless steels in the Fe-Cr-Ni, Fe-Cr-Mn-N, Fe-Cr-Mn-Ni-N systems generally contai ning C below 0,1%. If for the stainless austenite steels there are limits in C in terms of deformability, mashining by cutting tools, corrosion resistance, etc. in the better part of the cases with cast alloys those limits fall off. On the other hand, the attempt to transfer the results from the deformable to the cast steels is very risky, because of the differences in structure formation. A part from several studies of the author, there are almost no other data about the possibility of combined use of C ad N for strengthening the basic Cr-Mn austenite. There are no data about cast alloys with above equilibrium content of N when Cr is below 12-14%, as well as about high-chromium ones above 14-16% and above 0,4-0,8% of C. There is lack of data about cast-iron in that system. The results are disclosed in patents: RB31141 and RB51734. The basic factor determining wear resistance is phase composition, esp., chemical composition. At the present stages of research there is on common theory explaining the mechanism of wearing processes: cutting, grinding, friction, wearing hidroerosion, cavitation, erosion and additional corrosion. Wearing may be: pure abrasive, hydroabrasive, in media with different PH, esp. with different pressure: striking, folding, etc. Influence exerts also the metallurgical treatment of the melt conditions of crystallisation and the regime of thermal treatment. The diversity of wearing reflects on the structure formation, changes in which create difficulties in the determination of regularities between phase(structure) and chemical com position and wearing as well as in the choice of suitable composition in practice, regime and methods of treatment. Compromises between contradictory properties should often the made,.e.g. hardness, resilience etc. In rising wear resistance phases and structure compositions go in the following order: ferrite, perlite, troostite, zorbite. Austenite has been insufficiently studied and is given contradictory estimates. Besides austenite of the Cr18Ni10 type is corrosion-resistant, but poorly wear resistant and austenite of the Hat field steel type C110Mn13 is highly resistant under strike wearing and possesses low corrosion and ther mal resistance. The efforts to improve wear resistance of C110Mn13 with carbide-formators and even stabilisers gave no important results. It seems that until recently scientist have considered C the most important and single element which determines wear resistance of steels of the Hatfield type. Hence, it is expected that strengthening should improve wear resistance. Strengthenig uder alloying (etc), additional treatment and use. Combining Cr and Mn and C, N along with other elements very succeful combination of strength and heat resistance,wear resistance, etc. The production of wear resistant alloys is a topical problem of world significance. Needs are rising. This is a resource and environmental issue. There are no references about wear-resistant non- nickel alloys of the studied system, about the influence of the basic factors, pressure ad different types of heat treatment upon wear resistance. The paper presents part of the initial results of the investigations concerning the possibilities to produce wear resistant austenitic alloys of higher wear resistance than that of Hatfield’s (of the type C110Mn13) The effects of the basic components(C,N,SC+N,Cr,Mn) and crystalisation pressure on the wearresistance are studied. The results apply to states:after austeitization and quenching from 1150oC/H2O, ageing 700o C and after cooling at minus 65oC and they are protected by athors sertifications (patents) RB31141 and RB51734. It is obtained (the1-st time) high strength alloys with better wearresistance than that C110Mn13

 

ON SOME PROBLEMS OF HEAT TREATMENT AND STRUCTURE FORMATION OF NOVEL ALLOYS DESIGNED FOR GENERAL AND SPECIALISED MACHINE BUILDING Dr.Eng.Bogomil Velikov Kolev- Institute of Metal Science(IMS), Bulgarian Academy of Sciences(BAS) 67 ”Shipchensky prohod’’ str., 1574 Sofia, Bulgaria The paper presents in general framework a part of by now obtained results of the authors works in the period 1974-2001 about possibilities for obtaining new high-strength and wear-resistant cast alloys on Fe-C basis - complex alloyed steels and cast iron of different systems with differentstructure. Bulgarian methods with gas counter pressure (MOMGP) presents a fundamental innovation for great potential possibilities to develop and solve actual- priority Global problems of Mankind; creation of technologic and ecological as well as economically profitable machines and devices, new materials (alloys) and their products. One of the most perspective directions of MOMGP is creation of new machine-building materials(steels and cast iron), alloyed with gaseous (volatile) elements - Nitrogen and others. Of all known methods for improvement of structure and properties of the alloys on Ferro-basis the most effective is alloying. MOMGP outlined the principal fundamental possibilities and directions for development of the new gaseous metallurgy with volatile elements and substances. Nitrogen as the most common in Nature gas and residual product of a number of industrial production, processing the unique property to substitute expensive and deficit elements like: Ni, Cu,Co, (Mn) etc. and to improve some physic-mechanical and exploitation characteristics in times, not in percentage, completely corres- ponds to some of the challenges and the outlined Global problems of Mankind for the present and future, For unexplainable reasons the efforts of scientists are concentrated mainly on the production N alloying steels for deformation. Up to now investigations in the IMS-BAS based on the unique possibilities of the methods(MOMGP) for producing non deformable alloys (cast alloys for foundry) are considerably greater. The general results are presents of the investigations on structure formation of some high strength and wearresistant complex alloyed alloys of different systems on Fe-C bases after solidification in sand moulds and after austenitization and quenching, followed by heating and cooling(ageing) within the range of 300-500-1000oC .The paper includes summary of generalised theoretical and practical results from the next problems: 1.Effects of pressure and N on structure formation of Fe-C based cast alloys-theoretical and experimental results. 2. Summary of some investigation results on the structure formation :2.1. Austenite cast alloys in Fe-Cr-Mn-C-N and Fe-Cr-Mn-C systems. The structure have been examined after casting, austenitization and quenching. In general the structure may be evaluated as solid phase reaction. 2.Alloys of the Fe-Cr-C-N system. 2.3. Complex alloyed cast alloys in other metal systems. 2.4.Thermal stability of austenite quenched cast alloys of the Fe-Cr-Mn-C-N, Fe-Cr-Mn-C, Fe-Mn-Cr-C-N, Fe-Mn-Cr-C, Fe-Mn-C-N and Fe-Mn-C (Fe-Mn-N), Fe-Cr-C-N systems An attempt to be developed the principal processes of thermal stability under heating and cooling of austenitized and quenched Ni free austenite alloys. The work presents summary of theoretical and experimental results on the ageing of this alloys. 3.Somme importance properties (physic-mechanical, wear resistance, hardenabi lity, etc). General results. 4.Industrial testing and application fields 7.Development, perspectives and prognostication on production of new complex alloyed cast alloys. The intensive progress of world science imposes the necessity to create new materials and alloys with high physico-mechanicdl and exploitation characteristics with simultaneous decrease in material energy and other expenses for achieving high quality. Development of machine building as a strategic sector is inevitably connected to the creation of ever newer and more effective technologic and ecological proces- ses in foundry. At the end of the 20-Th. and the beginning of 21-St century tradition metallurgic and foun- ding technologies are exhausted in their possibilities to solve these complex issues. From the three ther- mo dynamic factors (composition, temperature and pressure), characterising and defining processes and phenomena in substances (the Nature),and properties of materials (alloys) in classic technologies are practically used only the first two. If studying and applying of the possibilities of vacuum technologies are developed well enough vacuum technologies, then the study and application of the possibilities of pressure, still at an initial stage seems to be very perspective, having in mind the challenges of the 21-St century.
HEAT TREATMENT AND SUGGESTIONS FOR APPLICATION OF NEW COMPLEX ALLOYED CAST ALLOYS OF THE Fe-Cr-C-(N) SYSTEM Dr.Eng.Bogomil Velikov Kolev- Institute of Metal Science(IMS), Bulgarian Academy of Sciences(BAS) 67 ”Shipchensky prohod’’ str., 1574 Sofia, Bulgaria The better part of details in industrial condition work not only under abrasive, hydroabrasive, corrosion mechanic wearing, but also under complex dynamic wear. That’s why the study of mechanic characteristics of these alloys aiming to search possibilities for their improvement as well as to chose the appropriate composition is very important for the quality and efficiency of the alloys. This is connected with the solving some topical problems: lightening of machines and apparatuses decreasing the need of about, resources and energy, which become less on the earth Global ecology. The mechanic characteristics of Cr alloyed casting alloys depend on many factors of which very significant are: chemical composition, crystallisation and thermal treatment conditions. These factors determine the character of the carbide (K) and nitride (N) and carbonitride (KN) phases and the basic metal matrix. The pressure, resp. the absorbed under its influence. N sharply refine structure along with the increase of cooling rate. The information about mechanic characteristics of casting alloys of Fe-Cr-C system connected with influence of chemical composition and thermal treatment is very scarce and for casting alloys of Fe-Cr-C-N system there are no data. One of the basic problems is that high C casting alloys of that system N free are difficulty to treating cutting instruments. The long years of observation show that N improves mashinability and sharply decreases the affinity towards crashes and slots, since under crystallisationN-phases are formed which have bigger hardness, than K and take stresses easily from phase transitions. We suppose that in cutting N phases have an lubricant role very much like graphite. In patents RB25568; 26110 49451 there is a concrete worked-out regime which allows cutting wearing, making aperture, etc. These alloys aren’t used in practices without thermal treatment. On importance for it are 3 factors: austeitization, duration, situation of critic points and ToC of quenching. First factor depends an alloying degree with elements making solid solutions for replacement. N doesn’t influence. The rest factor dependable on N. The paper includes summarised results: 1. There are results presented of the research on influence on basic components (Cr, C, N) on mechanic characteristics of alloyed and heat treated wear-resistant complex alloys of the Fe-Cr-C-(N) system: Rockwell’s hardness, strength tensile(sB), strength bending (sbend.) and impact strength (ak). The regularities drawn during testing enable the right choice of a proper chemical composition for specific casts according to specific working conditions: the type of wearing and pressure. 2.Hardness (HRC) and impact strength (auk) are the most important mechanic characteristics which determine the application of complex alloyed alloys of the Fe-Cr-C and Fe-Cr-C-N systems. There have bee presented some graphic about the influence of temperature (ToC) during quenching and tempering on (HRC) and (ak) of some typical casting complex alloyed, wear resistant alloys of the Fe-Cr-C-N system. An opposite influence of the ToC during quenching on the variation of HRC and has been determined.. This necessitates a choice of HRC and ak according to working conditions in production, esp. to pressure. 3.Hardenability is an important requirement particularly for thick wall casting under abrasive, hydroabrasive, impact abrasive and corrosion mechanic wear. On the basis of the author’s methods, equipment and installation for haredenability testing of the high hardening alloys the experimental results obtained comprise a wide rage of wear resistant complex alloyed alloys of the Fe-Cr-C-(N) system, summarised in several generalised graphical dependencies. 4.The basic exploitation means of complex alloyed cast alloys of the systems Fe-Cr-C and Fe-Cr-C- with and without additional alloying is wear resistanc. During last round 15 years data show cast iron of system Fe-Cr-C (without N) are said to be alternative of wearresistance materials for working in abrasion conditions. Data for their phisicomechanic and exploitation characteristics are rare expecially by observation. There are no data for wear resistance complex alloyed cast alloys of system Fe-Cr-C-N, as well as influence of basic components on it. Result of laboratory study are confirmed by tests in industrial conditions on concrete casts. NEW HIGH STRENGTH AND WEAR RESISTANT N- DOPED AUSTENITIC STEELS AND CAST IRONS Dr.Eng.Bogomil Velikov Kolev- Institute of Metal Science(IMS), Bulgarian Academy of Sciences(BAS) 67 ”Shipchensky prohod’’ str., 1574 Sofia, Bulgaria A problem of high interest in the present development of engineering is the production of cast alloys of the austenite class that have higher values of the relative yield strength (s02). The value of s02 of classical austenite cast steels of the Hatfield type C110Mn13 are law (up to 35-40.107Pa). The value of s02 in the classical Cr-Ni austenite cast alloys type Cr18Ni9Ti are lawyer. Of all methods for strengthening (marten site transformation, cold deformation, explosive strengthening, thermomechanical and thermociclic treat ment, ageing, intermetal strengthening, etc.) the most efficient one is alloying..C and N can be used not only as substitutes for expensive and deficient elements (Co,Ni,Mn,Cu,Zn etc.) as well as austeitisators and stabilisators of the g-solid solution, but also as elements increasing mechanical characteristics. In other works on the same subject usually present results of studies on mechanical characteristics after deformation of stainless steels in the Fe-Cr-Ni, Fe-Cr-Mn-N, Fe-Cr-Mn-Ni-N systems generally contai ning C below 0,1%. If for the stainless austenite steels there are limits in C in terms of deformability, mashining by cutting tools, corrosion resistance, etc. in the better part of the cases with cast alloys those limits fall off. On the other hand, the attempt to transfer the results from the deformable to the cast steels is very risky, because of the differences in structure formation. A part from several studies of the author, there are almost no other data about the possibility of combined use of C ad N for strengthening the basic Cr-Mn austenite. There are no data about cast alloys with above equilibrium content of N when Cr is below 12-14%, as well as about high-chromium ones above 14-16% and above 0,4-0,8% of C. There is lack of data about cast-iron in that system. The results are disclosed in patents: RB31141 and RB51734. The basic factor determining wear resistance is phase composition, esp., chemical composition. At the present stages of research there is on common theory explaining the mechanism of wearing processes: cutting, grinding, friction, wearing hidroerosion, cavitation, erosion and additional corrosion. Wearing may be: pure abrasive, hydroabrasive, in media with different PH, esp. with different pressure: striking, folding, etc. Influence exerts also the metallurgical treatment of the melt conditions of crystallisation and the regime of thermal treatment. The diversity of wearing reflects on the structure formation, changes in which create difficulties in the determination of regularities between phase(structure) and chemical com position and wearing as well as in the choice of suitable composition in practice, regime and methods of treatment. Compromises between contradictory properties should often the made,.e.g. hardness, resilience etc. In rising wear resistance phases and structure compositions go in the following order: ferrite, perlite, troostite, zorbite. Austenite has been insufficiently studied and is given contradictory estimates. Besides austenite of the Cr18Ni10 type is corrosion-resistant, but poorly wear resistant and austenite of the Hat field steel type C110Mn13 is highly resistant under strike wearing and possesses low corrosion and ther mal resistance. The efforts to improve wear resistance of C110Mn13 with carbide-formators and even stabilisers gave no important results. It seems that until recently scientist have considered C the most important and single element which determines wear resistance of steels of the Hatfield type. Hence, it is expected that strengthening should improve wear resistance. Strengthenig uder alloying (etc), additional treatment and use. Combining Cr and Mn and C, N along with other elements very succeful combination of strength and heat resistance,wear resistance, etc. The production of wear resistant alloys is a topical problem of world significance. Needs are rising. This is a resource and environmental issue. There are no references about wear-resistant non- nickel alloys of the studied system, about the influence of the basic factors, pressure ad different types of heat treatment upon wear resistance. The paper presents part of the initial results of the investigations concerning the possibilities to produce wear resistant austenitic alloys of higher wear resistance than that of Hatfield’s (of the type C110Mn13) The effects of the basic components(C,N,SC+N,Cr,Mn) and crystalisation pressure on the wearresistance are studied. The results apply to states:after austeitization and quenching from 1150oC/H2O, ageing 700o C and after cooling at minus 65oC and they are protected by athors sertifications (patents) RB31141 and RB51734. It is obtained (the1-st time) high strength alloys with better wearresistance than that C110Mn13  



Гласувай:
0



Няма коментари
Вашето мнение
За да оставите коментар, моля влезте с вашето потребителско име и парола.
Търсене

За този блог
Автор: bogomil
Категория: Други
Прочетен: 2027146
Постинги: 452
Коментари: 1153
Гласове: 1970
Календар
«  Март, 2024  
ПВСЧПСН
123
45678910
11121314151617
18192021222324
25262728293031