U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Publications by:

Search Title, Abstract, Conference, Citation, Keyword or Author
Displaying 26 - 50 of 81

Influence of Heating Rate on Flow Stress in High-Speed Machining Processes

April 1, 2004
Author(s)
Timothy J. Burns, Robert W. Ivester, Michael Kennedy, Richard L. Rhorer, Matthew A. Davies, Howard Yoon, Lyle E. Levine, Richard J. Fields, D Basak, Eric P. Whitenton
For several decades, a major focus of machining research has been the measurement and prediction of temperature. Here, the influence of the rate of heating on the flow stress, and the implications of this for finite-element modeling of high speed metal

Thermal Imaging of Metals in a Kolsky-Bar Apparatus

October 1, 2003
Author(s)
Howard W. Yoon, D Basak, Richard L. Rhorer, Eric P. Whitenton, Timothy J. Burns, Richard J. Fields, Lyle E. Levine
For materials testing at elevated temperatures, we describe the design and the development of a resistively heated Kolsky-bar apparatus. The temperature of the sample is determined by non-contact thermometry and the spatial temperature gradients in the

Kolsky Bar With Electrical Pulse Heating of the Sample

June 1, 2003
Author(s)
Eric P. Whitenton, Michael Kennedy, Matthew A. Davies, Gerald V. Blessing, Brian S. Dutterer, Richard L. Rhorer, Howard W. Yoon, Lyle E. Levine, Richard J. Fields, D Basak, Timothy J. Burns
The accuracy of simulations for modeling of machining processes is often limited due to insufficient knowledge of the material properties during machining, which can involve strain rates on the order of 104 per second or higher, plus rapid material heating

Receptance Coupling for High-Speed Machining Dynamics Prediction

February 1, 2003
Author(s)
T L. Schmitz, Timothy J. Burns
We apply receptance coupling techniques to predict the tool-point frequency response for high-speed machining applications. Building on early work of Duncan, Bishop and Johnson, and more recent work of Ewins, et al., we develop an analytic expression for

Calibrated thermal microscopy of the tool-chp interface in machining

January 1, 2003
Author(s)
Matthew A. Davies, Howard W. Yoon, Tony L. Schmitz, Timothy J. Burns, Michael Kennedy
This paper presents the results of calibrated, microscopic measurement of the temperature fields at the tool-chip interface during the steady-state, orthogonal machining of AISI 1045 steel. The measurement system consists of a nearly diffraction limited

Constitutive Model Data for Machining Simulation Using the NIST Pulse-Heat Kolsky Bar

January 1, 2003
Author(s)
Eric P. Whitenton, Michael Kennedy, Matthew A. Davies, Gerald V. Blessing, Brian S. Dutterer, Richard L. Rhorer, Howard W. Yoon, Richard J. Fields, D Basak, Timothy J. Burns
A new facility for dynamic material testing using a traditional Kolsky bar with the addition of controlled electrical-resistive pulse heating has been established at the National Institute of Standrds and Technology (NIST). Dynamic stress-strain data have

Thermal Imaging of Metals in a Kolsky-Bar Apparatus

January 1, 2003
Author(s)
Eric P. Whitenton, Richard L. Rhorer, Howard W. Yoon, D Basak, Richard J. Fields, Lyle E. Levine, Timothy J. Burns
For materials testing at elevated temperatures, we describe the design and the development of a resistively heated Kolsky-bar apparatus. The temperature of the sample is determined by non-contact thermometry and the spatial temperature gradients in the

Regenerative Stability Analysis of Highly Interrupted Machining

May 1, 2002
Author(s)
Matthew A. Davies, Jon R. Pratt, Brian S. Dutterer, Timothy J. Burns
We discuss theoretical and experimental work that supports the use of very low radia immersion in the high-speed milling of difficult-to-machine materials, such as titanium alloys. Our theory is based upon modeling the cutting process by a kicked harmonic

Stability Prediction For Low Radial Immersion Milling

May 1, 2002
Author(s)
Matthew A. Davies, Jon R. Pratt, Brian S. Dutterer, Timothy J. Burns
Traditional regenerative stability theory predicts a set of optimally stable spindle speeds at integer fractions of the national frequency of the most flexible mode of the system. The assumptions of this theory become invalid for highly interrupted

On Repeated Adiabatic Shear Band Formation During High-Speed Machining

April 1, 2002
Author(s)
Timothy J. Burns, Matthew A. Davies
We compare the repeated adiabatic shear band formation that takes place at sufficient large cutting speeds in a number of materials during high speed machining operations with the more well known formation of a single shear band that often takes place at