scholarly journals Effects of lubricant and temperature on friction coefficient during hot forging of Nimonic 115 superalloy

2011 ◽  
Vol 49 (05) ◽  
pp. 375-383 ◽  
Author(s):  
D. SHAHRIARI ◽  
M. H. SADEGHI ◽  
G. R. EBRAHIMI ◽  
K. T. KIM
Keyword(s):  
Friction Coefficient ◽  
Hot Forging ◽  
Nimonic 115

The Effect of Tool Surface Treatment on Friction in Hot Forging Process

2009 ◽  
Author(s):  
Varunee Premanond ◽  
Ratchanee Hato ◽  
Pakorn Chumrum ◽  
Jiraporn Sripraserd
Keyword(s):  
Friction Coefficient ◽  
Surface Treatment ◽  
Plasma Nitriding ◽  
Surface Condition ◽  
Hot Forging ◽  
Minor Effect ◽  
Forging Process ◽  
Tool Surface ◽  
Vacuum Nitriding ◽  
Hot Forging Process

This work considers the influences of various types of die surface treatment, lubricants and temperature on friction for hot forging process of brass. Well-known ring compression test were carried out to evaluate friction coefficient for various conditions. Tool material was hot work tool steel H13 and workpiece material was brass C3771. Tool surface condition selected were normal hardening, treated by hard chrome, plasma nitriding and vacuum nitriding. Tests were conducted with and without lubricants at elevated temperature between 400–600°C. The results of experiments without lubricant show that friction coefficient is reduced when using die with treated surface regardless of working temperature. The influences of surface treated on die are not significant when forming under lubricated condition. In other word, lubricant has minor effect to reduce friction when the treated tools are employed. However, graphite in water was found to be almost compatible lubricant to graphite in oil when forming by tool which is treated by vacuum nitriding. The hardness and roughness of tool surfaces are found no relevance to friction coefficient in this work.

The Method for Determining the Friction Coefficient in Relation to the Hot Forging Processes

2019 ◽  
Vol 822 ◽  
pp. 137-143
Author(s):  
Alexander I. Khaimovich ◽  
Yaroslav A. Erisov ◽  
Sergey Surudin ◽  
Ilia Petrov ◽  
Cho Pei Jiang ◽  
...  
Keyword(s):  
Experimental Data ◽  
Friction Coefficient ◽  
Relative Error ◽  
Theoretical Calculations ◽  
Hot Forging ◽  
Relative Volume ◽  
Friction Coefficients

A method for determining the friction coefficient was developed and experimentally tested by comparing theoretical calculations of the relative volume of radial channels filling with various convergence angles of generating line for various friction coefficients and experimental data on the value of filling these channels. Relative volume of metal extruded into the channel was selected as criterion for simulation the channel filling conditions depending on the friction coefficient. Relative error of the experiment results doesn’t exceed 6% according to the linearized models of this criterion.

Study on the Formability and Friction of Hot Forging Process of a Spur Gear Shaft for Manufacturing Engineering

2012 ◽  
Vol 583 ◽  
pp. 251-254
Author(s):  
Guang Chun Wang ◽  
Bin Hai Hao ◽  
Fu Xiao Pei ◽  
Tao Wang
Keyword(s):  
Friction Coefficient ◽  
Initial Temperature ◽  
Hot Forging ◽  
Spur Gear ◽  
Billet Temperature ◽  
Forging Process ◽  
Initial Billet ◽  
Manufacturing Engineering ◽  
Hot Forging Process ◽  
Good Agreement

Hot forging processes of a spur gear shaft with three billet sizes are simulated using FEM. The billet with size of φ36*60 has the best formability in hot forging the spur gear shaft. The effects of the initial billet temperature and the friction coefficient on the hot forging formability of the spur gear shaft are obtained respectively through simulation. Hot forging experiments are carried out and experimental results show good agreement with those in simulation. At last, the reasonable hot forging parameters of the spur gear shaft for manufacturing engineering are suggested as follows: billet size of φ36*60, billet initial temperature of 1050°C and friction coefficient of 0.3.

Coherency loss in γ' precipitates in nickel-base superalloy

1983 ◽  
Vol 41 ◽  
pp. 244-245
Author(s):  
R. A. Ricks ◽  
Angus J. Porter
Keyword(s):  
Lattice Mismatch ◽  
Lattice Parameter ◽  
Nickel Base Superalloy ◽  
Large Size ◽  
The Matrix ◽  
Nimonic 80A ◽  
Interfacial Dislocations ◽  
Nickel Base ◽  
Coherency Loss ◽  
Nimonic 115

During a recent investigation concerning the growth of γ' precipitates in nickel-base superalloys it was observed that the sign of the lattice mismatch between the coherent particles and the matrix (γ) was important in determining the ease with which matrix dislocations could be incorporated into the interface to relieve coherency strains. Thus alloys with a negative misfit (ie. the γ' lattice parameter was smaller than the matrix) could lose coherency easily and γ/γ' interfaces would exhibit regularly spaced networks of dislocations, as shown in figure 1 for the case of Nimonic 115 (misfit = -0.15%). In contrast, γ' particles in alloys with a positive misfit could grow to a large size and not show any such dislocation arrangements in the interface, thus indicating that coherency had not been lost. Figure 2 depicts a large γ' precipitate in Nimonic 80A (misfit = +0.32%) showing few interfacial dislocations.

Microstructure and Friction of Ion Beam Induced Amorphous Ti-Pd Alloys

1985 ◽  
Vol 55 ◽  
Author(s):  
J-P. Hirvonen ◽  
M. Nastasi ◽  
J. R. Phillips ◽  
J. W. Mayer
Keyword(s):  
Solid Solution ◽  
Friction Coefficient ◽  
Composition Range ◽  
Ion Beam ◽  
Amorphous Region ◽  
Transmission Electron ◽  
Solid Solution Region ◽  
Friction Measurements ◽  
Solution Region ◽  
High Equilibrium

ABSTRACTMultilayered samples of Ti-Pd with linearly varying compositions were irradiated by Xe ions at 600 keV. The induced microstructures were studied by using transmission electron microscopy and Rutherford backscattering. Mixing was found to be complete over the entire composition range, resulting in amorphous or amorphous plus crystalline structures except at the palladium-rich end, where a crystalline Pd-Ti solid solution was obtained. This is consistent with the high equilibrium solubility of Ti in Pd. In addition, significant coarsening of the microstructure caused by irradiation was found in this solid solution region.Friction measurements were carried out in air and water by using a polytetrafluoroethylene pin as a counterpart. In air the friction coefficient was independent of composition and microstructure after about 2000 passes. In water, however, after 600 passes the friction coefficient reached a steady-state value with a pronounced minimum over the amorphous region. This property was unchanged throughout the remaining 10000 passes.

A Quantitative Theory for the Computation of Tire Friction Under Severe Conditions of Sliding

1986 ◽  
Vol 14 (1) ◽  
pp. 44-72 ◽  
Author(s):  
C. M. Mc C. Ettles
Keyword(s):  
Friction Coefficient ◽  
Flash Temperature ◽  
Contact Conditions ◽  
Quantitative Form ◽  
Heating Effects ◽  
Rubber Friction ◽  
Viscoelastic Effects ◽  
Tire Friction ◽  
Pavement Friction ◽  
Metal Polymer

Abstract It is proposed that tire-pavement friction is controlled by thermal rather than by hysteresis and viscoelastic effects. A numerical model of heating effects in sliding is described in which the friction coefficient emerges as a dependent variable. The overall results of the model can be expressed in a closed form using Blok's flash temperature theory. This allows the factors controlling rubber friction to be recognized directly. The model can be applied in quantitative form to metal-polymer-ice contacts. Several examples of correlation are given. The difficulties of characterizing the contact conditions in tire-pavement friction reduce the model to qualitative form. Each of the governing parameters is examined in detail. The attainment of higher friction by small, discrete particles of aluminum filler is discussed.

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