THE DESIGN AND ANALYSIS OF EXPERIMENTS. By Oscar Kempthorne. New York, John Wiley and Sons, Inc., 1952. 631 pp. $8.50. This book by a teacher of statistics (as well as a consultant for \"experimenters\") is a comprehensive study of the philosophical background for the statistical design of experiment. It is necessary to have some facility with algebraic notation and manipulation to be able to use the volume intelligently. The problems are presented from the theoretical point of view, without such practical examples as would be helpful for those not acquainted with mathematics. The mathematical justification for the techniques is given. As a somewhat advanced treatment of the design and analysis of experiments, this volume will be interesting and helpful for many who approach statistics theoretically as well as practically. With emphasis on the \"why,\" and with description given broadly, the author relates the subject matter to the general theory of statistics and to the general problem of experimental inference. MARGARET J. ROBERTSON

The Design and Analysis of Experiments

[신간의 별자리x] 우리/미술, 그리고 ‘슬픔의 박물관’

Microstructure and mechanical properties of Al-7075 alloy processed by equal channel angular pressing combined with aging treatment

Modelling of the hot deformation behaviour of a titanium alloy using constitutive equations and artificial neural network

The hot compressive behaviors of a typical Ni-based superalloy are investigated by hot compression tests under the strain rates of 0001–1 s−1 and deformation temperatures of 920–1040 °C It is found that the dynamic recrystallization is the main softening mechanism for the studied superalloy during hot deformation The deformation temperature and strain rate have a significant influence on the dynamically recrystallized grain size Based on the experimental results, an inverse power law equation is established to describe the relationship between the dynamically recrystallized grain size and the steady-state flow stress A cellular automaton model with probabilistic state switches is established to simulate the dynamic recrystallization behaviors of the studied superalloy The flow stress and the dynamically recrystallized grain size can be well predicted by the established model Then, the dynamic recrystallization kinetic and the evolutions of the average grain size and grain boundary fraction are studied based on the simulated results The simulated results show that the dynamic recrystallization is initially heterogeneous, and gradually becomes homogeneous with the increase of the volume fraction of dynamic recrystallization With the increase of strain, the average grain size decreases, while the grain boundary fraction increases Furthermore, the average grain size and the grain boundary fraction remain relatively constant when the deformation is under a steady state

Study of dynamic recrystallization in a Ni-based superalloy by experiments and cellular automaton model

Equal channel angular pressing die to extrude a variety of materials

https://cyberleninka.org/article/n/1081807.pdf

Modeling the hot working behavior of near-α titanium alloy IMI 834

BT3-1 (Ti-6Al-2.5Mo-1.5Cr-0.5Fe-0.3Si) is a α+β titanium alloy that has been developed to meet the mechanical property requirements up to a temperature of 450 °C. The high temperature deformation behaviour of the material was evaluated by carrying out isothermal hot compression tests in the α+β, near β and β phase fields with a range of constant true strain rates. Using the flow behaviour data, processing map based on dynamic materials modeling was developed and the various domains in the map were correlated with microstructural mechanisms observed in the material. The material exhibits superplasticity when processed in the α+β regime while it experiences dynamic recrystallization (DRX) of β phase when processed above the β transus. When deformed close to the β transus, the material exhibits partial β recrystallization where the migrating boundaries of the β phase are pinned by the fine globular α particles distributed in the matrix. The activation energy and activation volume for deformation was evaluated to ascertain the rate controlling deformation mechanism. The results obtained are presented and discussed here

On the high temperature deformation behaviour of titanium alloy BT3-1

Effect of friction model in numerical analysis of equal channel angular pressing process

High temperature creep is an important property of titanium alloys used in aeroengines. Creep resistance of titanium alloys generally varies with heat treatment, temperature and cooling rate. Both the parameters affect the morphology and topology of the α (HCP) and β (BCC) phase present in the material. Various theories have been proposed in the literature to explain (i) the increase in creep strain with decreasing solution treatment temperature and (ii) the U-shaped variation of creep strain with cooling rate. Some of these theories are quite contradictory. An attempt is made here to systematically (a) evaluate and establish a direct microstructure–mechanical property correlation and (b) to explain the observed variation in the creep behaviour of a near-α titanium alloy IMI 834. The results obtained indicate that the observed U-shaped variation of creep curve is due to the counter acting nature of various microstructural features present in the material.

I. Balasundar

Papers

Equal channel angular pressing die to extrude a variety of materials

Modeling the hot working behavior of near-α titanium alloy IMI 834

On the high temperature deformation behaviour of titanium alloy BT3-1

Effect of friction model in numerical analysis of equal channel angular pressing process

Correlation between microstructural features and creep strain in a near-α titanium alloy processed in the α+β regime