D.C.:669.13;539.31

Traian Dumitrescu: Investigations regarding cast iron with special antifriction and elastic proprieties under working temperatures of internalcombustionmotors

Metalurgia (55) 2003, nr.9 p.5

The paper includes, in three chapters, the researches and experiments performed between 1995-1965, by one of the most reputedromanianspecialist, in the field of cast iron special antifriction and elastic proprieties , under working temperatures of internal combustion motors. In the first chapter, experiments in order to establish the manufacturing process of piston rings, for 2000HPaeroplanemotors, produced ofmicroalloyedwith Cr, Ni, W. Mo and modified grey cast iron, are presented; these experiments represent the backgrounder for establishing new assumptions regarding the basic structure and graphite role on piston rings characteristics and their behavior during operation. In the second chapter, experiments in order to perform a newspheroidalgraphite cast iron for high temperature piston rings production, are described, this cast iron isbased on4.0-5.5%Si allied ferrite as basic structure.

In the third chapter, the negative effect of ferrite on elasticity and thermal stability of the microstructure is presented. Investigations performed in this field demonstrate thateuthecticgraphite presented in the microstructure asinterdendritic,punctiformand under rosette shape, has no bad influence on such proprieties.

D.C.: 669.2/.8;669.25;669.24;669.782;669.331./192

Ion Cinca, Vasile Dănuţ Cojocaru, Lucia M. Angelescu:Intermettaliccompoundb(Ni₃Si) of Co-Ni-Siternarysystem

Metalurgia (55) 2003, nr.9, p.11

Eleven set of alloys were melted in vacuum, then poured into ingots. After pouring, they were heated up to 1000⁰C and vacuum treated. Then, samples fordifractometricanalysewereprelevated.

Using these experimental methods, themonofasicfieldb(Ni₃Si), belonging to ternary system Co-Ni-Siwas put in evidence.

D.C.:539.214;669.782;669.35;669.24

Riţi-Mihoc Emil, Dragoş Eugen:Investigationsregarding thedetermination of AT Si12CuNi alloytorsionplasticity

Metalurgia (55) 2003, nr.9, p.15

 This paper presents the measurements that have been done in order to establish the plasticity level of the aluminium alloy AT Si12CuNi. The experiments have been done by soliciting the material to a turning process on an installantion from the plastic deformation laboratory of the Sciences and Material Engineering Faculty of the Technical University in Cluj-Napoca.

The obtained results allow establishing the processing conditions by plastic deformation of this alloy.

D.C.: 669.35

Nicolae-Sorin Păun:Profitmaximisation forblistercopperproduction

Metalurgia (55) 2003, nr.9, p.20

In this paper a mathematical model for optimization of black copper production, in order to maximize the profit, is presented.

This model is based on a data basis for raw materials (copper concentrates, recovery products from copper metallurgy, copper wastes, etc.) processed under a smelting technological flow, including a hearth furnace and a Pierce-Smith converter.

 

Key words:information technology, concurrent engineering

Mariana Pop:Informationtechnology inconcurrentengineering

Metalurgia (55) 2003, nr.9, p.27

               CAD/CAM and CAE are terms which means Computer       Aided     Design/   Computer Aided Manufacturing and Computer Aided Engineering.

Computer Aided Design(CAD) can be defined as the use of computer systems to assist the creation, modification, analysis or optimization of a design.

Computer Aided Manufacturing(CAM) can be defined as the use of computer systems to plan, manage and control the operations of manufacturing plantthrough either direct or indirect computer interface with the plant’s resources.

The mechanical or manufacturing engineerwill, at some point of his or her career, have studied, used or been exposed to a variety of activities such as engineering drawing,design, numerical methods and analysis techniques, manufacturing techniques and organizational planning and control. There is a computer assisted means for all of these: Computer Aided Engineering(CAE).

               The aim of this paper is to present the main aplications of the information technology, knowing the importance of this domain in the activity of concurrent development of a product(by reducing the time to market).

D.C.: 539.319

Key words:remanent tensions, turbine rotor, relaxation, resistive electric tensometry, tensometric rosettes, blind hole method with deformation control

Tiberiu Mănescu, Camelia Bretotean Pinca,Ionuţ Copaci,Mircea Bejan:Remanenttensions in Francistypeturbinerotors. Monoblockalternative

 Metalurgia (55) 2003, nr.9, p.34

In very many practical situations, in great shape pieces appear wrights after woods the metal solidification, fists.

The study proposes the residual tensions determination, which reach different values in type Francis turbine rotors, monolith variant.

The experimental method used is the one of electrical resistive tensometry, by drilling (perforating), in industrial factory condition.