Effect of the thermal cycle of production of bimetallic cutting tools on the structure and mechanical characteristics of the fusion zone

The problems related to the wear of the cutting tools wear and the tools life at the machining of the stainless steels are very important due to the chemical and mechanical characteristics of these steels [1]. Over time the research have studied the causes which produce the cutting tool wear and the methods to improve the cutting tools durability, either by creating new types of materials for tools, either by the choice of tools geometric parameters and cutting regime [2, 3]. The purpose of this paper is the optimization of the cutting tool life and the cutting speed at the drilling of the stainless steels, in terms of the global indicator of the minimum machining cost.

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Young's Modulus Measurement of Chromium Electroplating

Advances in X-ray Analysis ◽

10.1154/s0376030800009216 ◽

1991 ◽

Vol 35 (A) ◽

pp. 527-535 ◽

Cited By ~ 1

Author(s):

Masaaki Ohtsuka ◽

Hideaki Hatsuok ◽

Yukio Hirose ◽

Hitoshi Ishii

Keyword(s):

Residual Stress ◽

Young’S Modulus ◽

Mechanical Characteristics ◽

Young's Modulus ◽

Cutting Tools ◽

Industrial Process ◽

Ray Method ◽

X Ray ◽

Chromium Electroplating ◽

Modulus Measurement

The electroplating of Cr has been an important industrial process for cutting tools, press machines and molds for casting. In spite of these, quite a few problems remain unsolved regarding the basic property. It is important to know the mechanical characteristics of Cr electroplated layers.In the present paper, the first part deals with the measurement of mechanical Young's modulus of Cr electroplated layers. The X-ray method was successfully applied to measure the X-ray Young's modulus and the residual stress on the Cr electroplated surface layer.

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Some Researches Regarding the Durability of the Metal Carbide Cutting Inserts Coated with Ti Thin Layers

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.657.281 ◽

2014 ◽

Vol 657 ◽

pp. 281-285

Author(s):

Ana Bădănac ◽

Octavian Lupescu ◽

Vasile Manole ◽

Sorin Popa

Keyword(s):

Thermal Field ◽

Mechanical Characteristics ◽

Cutting Tools ◽

Chemical Vapor ◽

Electric Arc ◽

Thin Layers ◽

Metal Carbide ◽

Cutting Inserts ◽

Cutting Processes ◽

Arc Evaporation

It is known that the unevenness of the cutting depths during the cutting processes, the different physico-mechanical characteristics of the processed materials, values as well as the parameters variation of the working regimes can lead a wear more or less pronounced of the used cutting tools. The lubricant presence in the cutting area may contribute to the friction and thermal field values reduction, affecting the wear processes. It can be said therefore that, the tools durability is influenced by all these factors, which requires decisions and actions to reduce the tools or/and the cutting inserts wear processes. In case of the cutting inserts are known many researches concerning their coverage with material (ions) by vacuum deposition, using methods as: electric arc evaporation, pulverization, ionic plating and chemical vapor deposition. Researches carried out by authors had consisted in making titanium deposition, in thin layer, on the cutting inserts surface in their hardening purpose. The results obtained consisted in a substantial increase of the durability for the used tools in cutting processes in report to those, whose cutting inserts were coated with titanium.

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Formability and Weld Zone Analysis of Tailor-Welded Blanks for Various Thickness Ratios

Journal of Engineering Materials and Technology ◽

10.1115/1.1857936 ◽

2005 ◽

Vol 127 (2) ◽

pp. 179-185 ◽

Cited By ~ 44

Author(s):

L. C. Chan ◽

S. M. Chan ◽

C. H. Cheng ◽

T. C. Lee

Keyword(s):

Fusion Zone ◽

Base Metal ◽

Mechanical Characteristics ◽

Thickness Ratio ◽

Microhardness Measurement ◽

Forming Limit ◽

Uniaxial Tensile ◽

Metallographic Study ◽

Major Strain ◽

Tailor Welded Blanks

Cold-rolled steel sheets of thicknesses ranging from 0.5 to 1.0 mm were used to produce tailor-welded blanks (TWBs) with various thickness ratios. In this study, the formability of the TWBs, as well as the mechanical characteristics of the weld zones, were analyzed experimentally under the effects of various thickness ratios of TWBs. The formability of the TWBs was evaluated in terms of three measures—failure mode, forming limit diagram, and minimum major strain, whereas the mechanical characteristics of the weld zones were investigated by tensile testing, metallographic study, and microhardness measurement. In particular, circular TWBs with different radii and cutoff widths were designed where all the welds were located in the center of the blanks and perpendicular to the principal strain direction. Nd:YAG laser butt-welding was used to weld the TWB specimens of different thickness ratios. The experimental findings in this study showed that the higher the thickness ratio of the TWBs, the lower the forming limit curve level, and the lower formability. The minimum major strain was clearly inversely proportional to the thickness ratio of the TWBs. On the other hand, the results of uniaxial tensile tests clearly illustrated that there was no significant difference between the tensile strengths of the TWBs and those of the base metals. The metallographic study demonstrated a difference of grain size in the materials at base metal, heat-affected zones, and fusion zone. The microhardness measurement indicated that the hardness in the fusion zone increased by about 60% of the base metal.

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Microstructural and mechanical characteristics of recycled hard metals for cutting tools

CIRP Annals ◽

10.1016/j.cirp.2010.03.052 ◽

2010 ◽

Vol 59 (1) ◽

pp. 133-136 ◽

Cited By ~ 8

Author(s):

M.G. Faga ◽

R. Mattioda ◽

L. Settineri

Keyword(s):

Mechanical Characteristics ◽

Cutting Tools ◽

Hard Metals

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Interfacial structures of dissimilar materials joined by capacitor-discharge welding

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100170402 ◽

1994 ◽

Vol 52 ◽

pp. 534-535

Author(s):

C. P. Doğan ◽

R. D. Wilson ◽

J. A. Hawk

Keyword(s):

Rapid Solidification ◽

Fusion Zone ◽

Dissimilar Materials ◽

Solidification Process ◽

Weld Interface ◽

Capacitor Discharge ◽

Fine Grained ◽

Iron Aluminum ◽

Conductive Ceramics ◽

Capacitor Discharge Welding

Capacitor Discharge Welding is a rapid solidification technique for joining conductive materials that results in a narrow fusion zone and almost no heat affected zone. As a result, the microstructures and properties of the bulk materials are essentially continuous across the weld interface. During the joining process, one of the materials to be joined acts as the anode and the other acts as the cathode. The anode and cathode are brought together with a concomitant discharge of a capacitor bank, creating an arc which melts the materials at the joining surfaces and welds them together (Fig. 1). As the electrodes impact, the arc is extinguished, and the molten interface cools at rates that can exceed 106 K/s. This process results in reduced porosity in the fusion zone, a fine-grained weldment, and a reduced tendency for hot cracking.At the U.S. Bureau of Mines, we are currently examining the possibilities of using capacitor discharge welding to join dissimilar metals, metals to intermetallics, and metals to conductive ceramics. In this particular study, we will examine the microstructural characteristics of iron-aluminum welds in detail, focussing our attention primarily on interfaces produced during the rapid solidification process.

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Correlation between dislocation, grain boundary and interface of duplex SS in stress corrosion cracking(SCC)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100177775 ◽

1990 ◽

Vol 48 (4) ◽

pp. 928-929

Author(s):

Wang Zheng-fang ◽

Z.F. Wang

Keyword(s):

Stainless Steel ◽

Thermal Cycle ◽

Secondary Phase ◽

Corrosion Cracking ◽

Coarse Grained ◽

Test Environment ◽

Fine Grained ◽

Evaluation Test ◽

Welding Thermal Cycle ◽

Micro Analysis

The main purpose of this study highlights on the evaluation of chloride SCC resistance of the material,duplex stainless steel,OOCr18Ni5Mo3Si2 (18-5Mo) and its welded coarse grained zone(CGZ).18-5Mo is a dual phases (A+F) stainless steel with yield strength:512N/mm2 .The proportion of secondary Phase(A phase) accounts for 30-35% of the total with fine grained and homogeneously distributed A and F phases(Fig.1).After being welded by a specific welding thermal cycle to the material,i.e. Tmax=1350°C and t8/5=20s,microstructure may change from fine grained morphology to coarse grained morphology and from homogeneously distributed of A phase to a concentration of A phase(Fig.2).Meanwhile,the proportion of A phase reduced from 35% to 5-10°o.For this reason it is known as welded coarse grained zone(CGZ).In association with difference of microstructure between base metal and welded CGZ,so chloride SCC resistance also differ from each other.Test procedures:Constant load tensile test(CLTT) were performed for recording Esce-t curve by which corrosion cracking growth can be described, tf,fractured time,can also be recorded by the test which is taken as a electrochemical behavior and mechanical property for SCC resistance evaluation. Test environment:143°C boiling 42%MgCl2 solution is used.Besides, micro analysis were conducted with light microscopy(LM),SEM,TEM,and Auger energy spectrum(AES) so as to reveal the correlation between the data generated by the CLTT results and micro analysis.

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