共查询到8条相似文献,搜索用时 0 毫秒
1.
This paper presents and discusses an experimental investigation of abrasive waterjet (AWJ) cutting of alumina ceramics with
controlled nozzle oscillation. Particular attention is paid to the effect of small oscillation angles on the various cutting
performance measures. It is found that nozzle oscillation at small angles can equally improve the major cutting performance
measures, if the cutting parameters are correctly selected. However, under high water pressures, high nozzle traverse speeds
and large oscillation frequencies, nozzle oscillation may cause a decrease in some major cutting performance measures, such
as surface finish. Plausible trends of cutting performance with respect to the process parameters are further considered.
Finally, a predictive mathematical model for the depth of cut is developed and verified. 相似文献
2.
Jun Wang 《Frontiers of Mechanical Engineering in China》2010,5(1):19-32
An experimental study of the depth of cut in multipass abrasive waterjet (AWJ) cutting of alumina ceramics with controlled
nozzle oscillation is presented. It is found that this cutting technique can significantly increase the depth of cut by an
average of 50.8% as compared to single pass cutting without nozzle oscillation under the corresponding cutting conditions
and within the same cutting time. Predictive models for the depth of cut are then developed. The modelling process starts
with single pass cutting using a dimensional analysis technique and the particle erosion theories applied to alumina ceramics,
before progressing to the development of the models for multipass cutting. The models are finally assessed both qualitatively
and quantitatively with experimental data. It is shown that the model predictions are in good agreement with the experimental
data with the average deviations of about 1%. 相似文献
3.
Predictive depth of jet penetration models for abrasive waterjet cutting of alumina ceramics 总被引:2,自引:0,他引:2
A study of the depth of jet penetration (or depth of cut) in abrasive waterjet (AWJ) cutting of alumina ceramics with controlled nozzle oscillation is presented and discussed. An experimental investigation is carried out first to study the effects of nozzle oscillation at small angles on the depth of cut under different combinations of process parameters. Based on the test conditions, it is found that nozzle oscillation at small angles can improve the depth of cut by as much as 82% if the cutting parameters are correctly selected. Depending on the other cutting parameters in this study, it is found that a high oscillation frequency (10–14 Hz) with a low oscillation angle (4–6°) can maximize the depth of cut. Using a dimensional analysis technique, predictive models for jet penetration when cutting alumina ceramics with and without nozzle oscillation are finally developed and verified. It is found that the model predictions are in good agreement with the experimental results with the average percentage errors of less than 2.5%. 相似文献
4.
5.
6.
A. A. El-Domiaty Dr A. A. Abdel-Rahman 《The International Journal of Advanced Manufacturing Technology》1997,13(3):172-181
Advanced engineering ceramic materials such as silicon carbides and silicon nitride have been used in many engineering applications. The abrasive waterjet is becoming the most recent cutting technique of such materials because of its inherent advantages.In the present study, two elastic-plastic erosion models are adopted to develop an abrasive waterjet model for cutting brittle materials. As a result, two cutting models based on fracture mechanics are derived and introduced. The suggested models predict the maximum depth of cut of the target material as a function of the fracture toughness and hardness as well as the process parameters.It is found that both models predict the same depth of cut within a maximum of 11%, for the practical range of process parameters used in the present study. The maximum depth of cut predicted by the suggested models are compared with published experimental results for three types of ceramics. The effect of process parameters on the maximum depth of cut for a given ceramic material is also studied and compared with experimental work. The comparison reveals that there is a good agreement between the models' predictions and experimental results, where the difference between the predicted and experimental value of the maximum depth of cut is found to be an average value of 10%.Nomenclature
C
abrasive efficiency factor, see equation (16)
-
C
1,C
2
c
1/4/3, c2/4/3
-
c
1,c
2
erosion models constants, see equations (1) and (2)
-
d
a
local effective jet diameter
-
d
j
nozzle diameter
- d
S
infinitesimal length along the kerf
-
f
1 (
E
)
function defined by equation (7)
-
f
2 (
E
)
function defined by equation (8)
-
f
3 (
e
)
function defined by equation (14)
-
g
1 (
E
)
f
1(
e
)/f
3
2
(
e
)
-
g
2 (
e
)
f
2(
e
/f
3
2
(
e
)
-
H
Vickers hardness of the target material
-
h
maximum depth of cut
-
K
c
fracture toughness of target material
-
k
kerf constant
-
M
linear removal rate, dh/dt
-
m
mass of a single particle
-
abrasive mass flow rate
-
water mass flow rate
-
P
water pressure
-
Q
total material removal rate, see equation (11)
-
R
abrasive to water mass flow rates
-
r
particle radius
-
S
kerf length
-
u
traverse speed
-
V
material volume removal rate (erosion rate)
- V
idealised volume removal by an individual abrasive particle
-
particle impact velocity
-
0
initial abrasive particle velocity
-
x,y
kerf coordinates
-
local kerf angle, Fig. 1
-
E
jet exit angle at the bottom of the workpiece, Fig. 1
-
particle density
-
w
water density
On leave from: Mechanical Engineering Department, Suez Canal University, Egypt.On leave from: Mechanical Power Engineering Department, Alexandria University, Egypt. 相似文献
7.
M. Kantha Babu O.V. Krishnaiah Chetty 《The International Journal of Advanced Manufacturing Technology》2006,29(5):532-540
This paper details the studies on the use of single mesh size garnet abrasives in abrasive waterjet machining for cutting
aluminum. The influence of three different single mesh size abrasives, pressure, traverse rate, and abrasive flow rate; on
depth of cut, top kerf width, bottom kerf width, kerf taper, and surface roughness are investigated. Experiments designed
using standard L9 orthogonal array and the analysis of variance helped in the determination of highly significant, significant
and weakly significant cutting parameters. Single mesh size abrasives are found to yield decreased surface roughness than
multi mesh size abrasives. Based on these studies, response equations are developed to predict the target parameters. Using
single mesh abrasives, a practitioner not only can cut faster but also achieve reduced surface roughness. 相似文献
8.
K.S. Amirthagadeswaran V.P. Arunachalam 《The International Journal of Advanced Manufacturing Technology》2006,29(5-6):532-540
This paper details the studies on the use of single mesh size garnet abrasives in abrasive waterjet machining for cutting
aluminum. The influence of three different single mesh size abrasives, pressure, traverse rate, and abrasive flow rate; on
depth of cut, top kerf width, bottom kerf width, kerf taper, and surface roughness are investigated. Experiments designed
using standard L9 orthogonal array and the analysis of variance helped in the determination of highly significant, significant
and weakly significant cutting parameters. Single mesh size abrasives are found to yield decreased surface roughness than
multi mesh size abrasives. Based on these studies, response equations are developed to predict the target parameters. Using
single mesh abrasives, a practitioner not only can cut faster but also achieve reduced surface roughness. 相似文献