1 Introduction SiCp/Al composites are rigid particle reinforced metal matrix composites due to their high specific strength and specific stiffness, low coefficient of linear expansion, good dimensional stability, good abrasion and heat resistance, and remeltability. It is widely used in aerospace, aerospace and automotive industries due to its advantages such as good quality and low price. Due to the addition of high-strength hard-brittle SiC ceramic particles in this material, the mechanical properties of the matrix material are greatly improved, and the macro-isotropy of the composite material is also a feature. On the other hand, it is precisely because of the addition of SiC reinforcing particles that the machinability of this composite material is deteriorated, and the tool wears abruptly during machining, and it is difficult to ensure the machining accuracy and the quality of the machined surface. Research shows that high-speed steel cutters and carbide cutters have become more and more inadequate in cutting SiCp/Al composites. Therefore, many scholars have devoted themselves to the research and development of new cutting tool materials suitable for machining SiCp/Al composites. Polycrystalline diamond (PCD) is a new type of super-hard tool material. The PCD tool is sintered from selected synthetic diamond microcrystals under high temperature and high pressure. Due to the addition of additives during the sintering process, diamond crystals are formed between TiC, SiC, Fe, Co, Ni, etc., are the bonding bridges of the main components. The diamond crystals are firmly embedded in the solid skeleton composed of bonding bridges in the form of covalent bonds, which greatly improves the hardness and toughness of the PCD. Therefore, the PCD tool not only has a high hardness of the diamond but also has a higher toughness than the single crystal diamond, and the blade base body also has a high bending strength. Turning metal-based silicon carbide particle reinforced composites with PCD tools is a sophisticated, high-efficiency new machining method. Many scholars have studied this, but most of them are limited to the use of PCD tools for ordinary machining. In recent years, the application of ultrasonic vibratory cutting methods to process difficult-to-machine materials has shown high processing accuracy and good quality, and its good processing performance has caused great concern. Ultrasonic vibration machining is gradually becoming an important means of precision and ultra-precision machining. one. Based on the general turning and ultrasonic vibration turning tests of SiCp/Al composites machined with PCD tools, the author conducted a preliminary discussion on the machining process of PCD cutters for ultrasonic vibration cutting of metal-based silicon carbide particle reinforced composites, and analyzed and compared cutting speeds and feed rates. The influence of cutting parameters such as cutting depth and cutting force on the cutting force, and the results of the tests and discussions have certain guiding significance for the cutting and processing of metal matrix composites (especially the machining of thin-walled and slender shaft parts). 2 cutting test conditions Machine: CA6140 ordinary lathe; cutter: PCD welding lathe tool; workpiece material: metal matrix composite SiCp / Al bar, casting, weight percentage 12%, particle size W14, bar diameter Ø42mm, length 150mm. Vibration device: A self-made longitudinal vibration device (amplitude of 15 μm, frequency of 20 kHz).
Figure 1 Cutting force measuring device cutting force measuring device (see Figure 1): The force measuring system adopts Beihang SDC-CJ4A resistance strain gauge dynamometer. The dynamometer has multiple ranges of selectable ranges. The measurement range used in the test is 0-500N and the measurement accuracy is 0.2N (which can meet the requirements of precision measurement). Because the frequency response range of the dynamometer is 0～3000Hz, although the requirements of general cutting force measurement can be met, the pulse waveform of cutting force with frequency up to 20kHz in ultrasonic vibration cutting cannot be measured. Therefore, the actual measured force in the test is the cutting force. average value. 3 Single-factor relationship between cutting force and cutting parameters Test and analysis Effect of cutting speed on cutting force Test and measurement
Table 1 Relationship between cutting force Fc and machine tool speed n Machine tool speed n(r/min) 60 90 180 305 Vibratory cutting force Fc(N) 12.27 13.16 16.91 25.25 Ordinary cutting force Fc(N) 33.9 33.25 30.27 33.26 To study the cutting speed Changes in the impact of ultrasonic vibration cutting force, in the cutting test, to maintain the feed f=0.08mm, cutting depth ap = 0.3mm unchanged, only to change the cutting speed, respectively, measuring machine tool speed n = 60r/min, 90r/min The cutting force Fc during ultrasonic vibration cutting and general cutting at 180r/min and 305r/min is shown in Table 1. results and analysis
Fig. 2 Relationship between cutting speed and cutting force The relationship between cutting speed and cutting force obtained from the test is shown in Fig. 2. As can be seen from the figure, the cutting force does not change much as the machine speed increases during normal cutting. In vibratory cutting, due to its pulse cutting effect, cutting is performed only for tc within a vibration period T. Therefore, the average cutting force Fc is tc/T of the pulse cutting force peak, and the effective cutting time tc becomes longer as the cutting speed increases. The average cutting force Fc also gradually increases. When the cutting speed is close to the critical cutting speed (ie, tc/T≈1), Fc=Fc (in this case, normal cutting state). It can be seen from the figure that the cutting force gradually increases as the rotation speed increases: when the rotation speed is 60r/min, the cutting force of the vibration cutting is only 1/3 of the ordinary cutting; with the increase of the rotation speed, the effective cutting time will follow. Increasing, when the rotational speed increases to 180r/min, the average cutting force of vibration cutting increases to approximately 1/2 of the ordinary cutting; when the rotating speed approaches the critical rotating speed, vibration cutting is converted into ordinary cutting. From this we can see that the test results are basically consistent with the theoretical analysis. Table 2 Relationship between cutting force Fc and feed rate f Feed rate f (mm/r) 0.08 0.12 0.20 Vibratory cutting force Fc(N) 13.00 22.40 52.40 Ordinary cutting force Fc(N) 35.37 45.98 65.87
Fig. 3 Relationship between feed and cutting force Effect of feed on cutting force Test and measurement To study the effect of feed change on ultrasonic vibration cutting force, in the cutting test, maintain the machine speed n=90 r/min, The cutting depth ap=0.3mm is constant, and only the feed amount f is changed. The cutting force Fc of the ultrasonic vibration cutting and the ordinary cutting at the feeding amount of f=0.08mm, 0.12mm, and 0.20mm is measured, and the test results are shown in Table 2. Results and analysis The relationship between the feed and cutting force obtained in the test is shown in Fig. 3. As can be seen from the figure, as the feed amount increases, the cutting resistance increases, the ordinary cutting force and the vibratory cutting force both increase, but the vibratory cutting force increases faster, which is due to the amount of feed. As the feed resistance increases, the amplitude of vibration cutting decreases, resulting in a faster increase in cutting force. Due to the large amount of feed during vibration cutting, the low frequency vibration of the tool holder may be caused. Therefore, the feed amount selected in this test is small to ensure the machining accuracy and the quality of the machined surface. Table 3 Relationship between cutting force Fc and depth ap Cutting depth ap (mm) 0.1 0.3 0.5 Vibratory cutting force Fc (N) 3.60 14.80 39.72 Ordinary cutting force Fc (N) 15.30 45.50 64.50
Fig. 4 Relationship between cutting depth and cutting force Influence of cutting depth on cutting force Test and measurement To study the effect of cutting depth change on ultrasonic vibration cutting force, in the cutting test, the machine speed was maintained at n=90 r/min, and the feed amount was f=0.08mm/r does not change, only the cutting depth ap is changed. The cutting force Fc of the ultrasonic vibration cutting and the ordinary cutting at depths of ap=0.1mm, 0.3mm, and 0.5mm were measured, and the results are shown in Table 3. Results and analysis The relationship between the depth of cut obtained by the test and the cutting force is shown in Figure 4. As can be seen from the figure, the cutting force is quite sensitive to changes in depth of cut. When the cutting depth ap<0.3mm, the vibratory cutting force is only 1/3 of the ordinary cutting force; when the cutting depth reaches 0.5mm, the vibratory cutting force and the ordinary cutting force gradually approach, indicating that with the increase of the cutting depth, the tool unit As the cutting load on the area increases, the tool amplitude decreases, the pulse cutting effect of vibration cutting weakens, and the average cutting force during vibration cutting increases. Comprehensive analysis of single-factor relationship between cutting force and cutting parameters in ordinary cutting and ultrasonic vibration cutting test results show that compared with ordinary turning, the average main cutting force Fc of ultrasonic vibration turning is significantly reduced. With a smaller amount of cutting, the decrease in Fc was particularly significant. Under ultrasonic vibration turning conditions, the cutting force increases steadily with the increase of cutting amount. The cutting force of ultrasonic vibration turning—the characteristics of cutting speed is obviously different from the cutting force—cutting speed characteristics that are exhibited due to built-up edge in ordinary cutting. Microscopic observations show that ultrasonic vibration turning does not produce built-up edge in the corresponding cutting speed range. When the cutting speed v is greater than the critical cutting speed, ultrasonic vibration turning still has the above characteristics; when v increases to a certain value, the increase of cutting force tends to be gentle. 4 vibration cutting aid of orthogonal cutting force and the cutting test parameters and test analysis of Table 4 Factors factor level table test speed (m / min) Feed (mm / r) depth of cut (mm) 4.24 0.08 0.10 1 horizontal level 2 8.48 0.10 0.30 Level 3 12.72 0.15 0.50 Multi-factor Orthogonal Test Scheme for the orthogonal cutting force of SiCp/Al metal matrix composites subjected to ultrasonic vibration turning. Through regression orthogonal analysis, the relationship between cutting force and various cutting parameters is discussed. Relationship and choose the most suitable vibration cutting parameters. Rotation speed, feed rate, and depth of cut are the three most important and independent parameters in the turning process, so the above three parameters are selected as orthogonal test factors. Use the L9 (23) orthogonal table as a three-factor, three-level orthogonal test (regardless of interaction) to establish the test factor level table shown in Table 4. Test results and analysis According to the cutting conditions listed in Table 4, the L9 (23) orthogonal table was used to obtain the cutting force test data shown in Table 5.
Table 5 cutting force test data Test serial number rotation speed
(m/min) Feed rate
(mm/r) depth of cut
(mm) Radial cutting force
(N) Main cutting force
(N) 1 4.24 0.08 0.10 4.18 2.58 2 4.24 0.10 0.30 10.30 7.03 3 4.24 0.15 0.50 24.30 36.14 4 8.48 0.08 0.30 13.76 8.14 5 8.48 0.10 0.50 23.00 30.00 6 8.48 0.15 0.10 10.18 3.12 7 12.72 0.08 0.50 27.47 33.30 8 12.72 0.10 0.10 6.29 4.00 9 12.72 0.15 0.30 10.56 8.00 Orthogonal regression analysis of the data in Table 5 yields the regression coefficient B, test parameter t, and test value F as
The regression equation is F=101.79v0.14f0.12ap1.35=61.69v0.14f0.12ap1.35 The F-test is used to test the effect of the regression equation because F=11.77>F0.05 (3,5)=5.41. The equation is quite significant. The t-test is used for each independent variable in the regression equation because t3 > 1, so the depth of cut is a non-negligible factor for cutting forces. From the index of the regression equation, it can be seen that the influence of f, v, ap on the cutting force is increasing. From the relationship between cutting forces and various factors, it can be known that the cutting force is basically proportional to the depth of cut, which is similar to the normal cutting rule; the amount of feed also has a positive effect on the cutting force, but the degree of influence on the cutting force is not as good as the depth of cut; the cutting speed is The influence of cutting force is greater than the feed rate, because with the increase of cutting speed, the effective cutting time of the tool during the vibration cycle increases, resulting in increased cutting force. 5 Conclusion Ultrasonic vibratory turning has a significant advantage of less average primary cutting force, compared to ordinary turning, with a small amount of cutting. When using ultrasonic vibration turning, under the premise of taking into account the processing efficiency, a small cutting speed should be properly selected to effectively reduce the cutting force, thereby reducing the deformation of the process system, in the processing of thin-walled parts, slender shafts and other rigid Satisfactory machining accuracy can be achieved on the part. According to the index depth ap, it can be seen that to reduce the cutting force, ap<1mm must be made, which also shows that ultrasonic vibration turning is particularly suitable for precision and ultra-precision machining.
Figure 1 Cutting force measuring device cutting force measuring device (see Figure 1): The force measuring system adopts Beihang SDC-CJ4A resistance strain gauge dynamometer. The dynamometer has multiple ranges of selectable ranges. The measurement range used in the test is 0-500N and the measurement accuracy is 0.2N (which can meet the requirements of precision measurement). Because the frequency response range of the dynamometer is 0～3000Hz, although the requirements of general cutting force measurement can be met, the pulse waveform of cutting force with frequency up to 20kHz in ultrasonic vibration cutting cannot be measured. Therefore, the actual measured force in the test is the cutting force. average value. 3 Single-factor relationship between cutting force and cutting parameters Test and analysis Effect of cutting speed on cutting force Test and measurement
Table 1 Relationship between cutting force Fc and machine tool speed n Machine tool speed n(r/min) 60 90 180 305 Vibratory cutting force Fc(N) 12.27 13.16 16.91 25.25 Ordinary cutting force Fc(N) 33.9 33.25 30.27 33.26 To study the cutting speed Changes in the impact of ultrasonic vibration cutting force, in the cutting test, to maintain the feed f=0.08mm, cutting depth ap = 0.3mm unchanged, only to change the cutting speed, respectively, measuring machine tool speed n = 60r/min, 90r/min The cutting force Fc during ultrasonic vibration cutting and general cutting at 180r/min and 305r/min is shown in Table 1. results and analysis
Fig. 2 Relationship between cutting speed and cutting force The relationship between cutting speed and cutting force obtained from the test is shown in Fig. 2. As can be seen from the figure, the cutting force does not change much as the machine speed increases during normal cutting. In vibratory cutting, due to its pulse cutting effect, cutting is performed only for tc within a vibration period T. Therefore, the average cutting force Fc is tc/T of the pulse cutting force peak, and the effective cutting time tc becomes longer as the cutting speed increases. The average cutting force Fc also gradually increases. When the cutting speed is close to the critical cutting speed (ie, tc/T≈1), Fc=Fc (in this case, normal cutting state). It can be seen from the figure that the cutting force gradually increases as the rotation speed increases: when the rotation speed is 60r/min, the cutting force of the vibration cutting is only 1/3 of the ordinary cutting; with the increase of the rotation speed, the effective cutting time will follow. Increasing, when the rotational speed increases to 180r/min, the average cutting force of vibration cutting increases to approximately 1/2 of the ordinary cutting; when the rotating speed approaches the critical rotating speed, vibration cutting is converted into ordinary cutting. From this we can see that the test results are basically consistent with the theoretical analysis. Table 2 Relationship between cutting force Fc and feed rate f Feed rate f (mm/r) 0.08 0.12 0.20 Vibratory cutting force Fc(N) 13.00 22.40 52.40 Ordinary cutting force Fc(N) 35.37 45.98 65.87
Fig. 3 Relationship between feed and cutting force Effect of feed on cutting force Test and measurement To study the effect of feed change on ultrasonic vibration cutting force, in the cutting test, maintain the machine speed n=90 r/min, The cutting depth ap=0.3mm is constant, and only the feed amount f is changed. The cutting force Fc of the ultrasonic vibration cutting and the ordinary cutting at the feeding amount of f=0.08mm, 0.12mm, and 0.20mm is measured, and the test results are shown in Table 2. Results and analysis The relationship between the feed and cutting force obtained in the test is shown in Fig. 3. As can be seen from the figure, as the feed amount increases, the cutting resistance increases, the ordinary cutting force and the vibratory cutting force both increase, but the vibratory cutting force increases faster, which is due to the amount of feed. As the feed resistance increases, the amplitude of vibration cutting decreases, resulting in a faster increase in cutting force. Due to the large amount of feed during vibration cutting, the low frequency vibration of the tool holder may be caused. Therefore, the feed amount selected in this test is small to ensure the machining accuracy and the quality of the machined surface. Table 3 Relationship between cutting force Fc and depth ap Cutting depth ap (mm) 0.1 0.3 0.5 Vibratory cutting force Fc (N) 3.60 14.80 39.72 Ordinary cutting force Fc (N) 15.30 45.50 64.50
Fig. 4 Relationship between cutting depth and cutting force Influence of cutting depth on cutting force Test and measurement To study the effect of cutting depth change on ultrasonic vibration cutting force, in the cutting test, the machine speed was maintained at n=90 r/min, and the feed amount was f=0.08mm/r does not change, only the cutting depth ap is changed. The cutting force Fc of the ultrasonic vibration cutting and the ordinary cutting at depths of ap=0.1mm, 0.3mm, and 0.5mm were measured, and the results are shown in Table 3. Results and analysis The relationship between the depth of cut obtained by the test and the cutting force is shown in Figure 4. As can be seen from the figure, the cutting force is quite sensitive to changes in depth of cut. When the cutting depth ap<0.3mm, the vibratory cutting force is only 1/3 of the ordinary cutting force; when the cutting depth reaches 0.5mm, the vibratory cutting force and the ordinary cutting force gradually approach, indicating that with the increase of the cutting depth, the tool unit As the cutting load on the area increases, the tool amplitude decreases, the pulse cutting effect of vibration cutting weakens, and the average cutting force during vibration cutting increases. Comprehensive analysis of single-factor relationship between cutting force and cutting parameters in ordinary cutting and ultrasonic vibration cutting test results show that compared with ordinary turning, the average main cutting force Fc of ultrasonic vibration turning is significantly reduced. With a smaller amount of cutting, the decrease in Fc was particularly significant. Under ultrasonic vibration turning conditions, the cutting force increases steadily with the increase of cutting amount. The cutting force of ultrasonic vibration turning—the characteristics of cutting speed is obviously different from the cutting force—cutting speed characteristics that are exhibited due to built-up edge in ordinary cutting. Microscopic observations show that ultrasonic vibration turning does not produce built-up edge in the corresponding cutting speed range. When the cutting speed v is greater than the critical cutting speed, ultrasonic vibration turning still has the above characteristics; when v increases to a certain value, the increase of cutting force tends to be gentle. 4 vibration cutting aid of orthogonal cutting force and the cutting test parameters and test analysis of Table 4 Factors factor level table test speed (m / min) Feed (mm / r) depth of cut (mm) 4.24 0.08 0.10 1 horizontal level 2 8.48 0.10 0.30 Level 3 12.72 0.15 0.50 Multi-factor Orthogonal Test Scheme for the orthogonal cutting force of SiCp/Al metal matrix composites subjected to ultrasonic vibration turning. Through regression orthogonal analysis, the relationship between cutting force and various cutting parameters is discussed. Relationship and choose the most suitable vibration cutting parameters. Rotation speed, feed rate, and depth of cut are the three most important and independent parameters in the turning process, so the above three parameters are selected as orthogonal test factors. Use the L9 (23) orthogonal table as a three-factor, three-level orthogonal test (regardless of interaction) to establish the test factor level table shown in Table 4. Test results and analysis According to the cutting conditions listed in Table 4, the L9 (23) orthogonal table was used to obtain the cutting force test data shown in Table 5.
Table 5 cutting force test data Test serial number rotation speed
(m/min) Feed rate
(mm/r) depth of cut
(mm) Radial cutting force
(N) Main cutting force
(N) 1 4.24 0.08 0.10 4.18 2.58 2 4.24 0.10 0.30 10.30 7.03 3 4.24 0.15 0.50 24.30 36.14 4 8.48 0.08 0.30 13.76 8.14 5 8.48 0.10 0.50 23.00 30.00 6 8.48 0.15 0.10 10.18 3.12 7 12.72 0.08 0.50 27.47 33.30 8 12.72 0.10 0.10 6.29 4.00 9 12.72 0.15 0.30 10.56 8.00 Orthogonal regression analysis of the data in Table 5 yields the regression coefficient B, test parameter t, and test value F as
The regression equation is F=101.79v0.14f0.12ap1.35=61.69v0.14f0.12ap1.35 The F-test is used to test the effect of the regression equation because F=11.77>F0.05 (3,5)=5.41. The equation is quite significant. The t-test is used for each independent variable in the regression equation because t3 > 1, so the depth of cut is a non-negligible factor for cutting forces. From the index of the regression equation, it can be seen that the influence of f, v, ap on the cutting force is increasing. From the relationship between cutting forces and various factors, it can be known that the cutting force is basically proportional to the depth of cut, which is similar to the normal cutting rule; the amount of feed also has a positive effect on the cutting force, but the degree of influence on the cutting force is not as good as the depth of cut; the cutting speed is The influence of cutting force is greater than the feed rate, because with the increase of cutting speed, the effective cutting time of the tool during the vibration cycle increases, resulting in increased cutting force. 5 Conclusion Ultrasonic vibratory turning has a significant advantage of less average primary cutting force, compared to ordinary turning, with a small amount of cutting. When using ultrasonic vibration turning, under the premise of taking into account the processing efficiency, a small cutting speed should be properly selected to effectively reduce the cutting force, thereby reducing the deformation of the process system, in the processing of thin-walled parts, slender shafts and other rigid Satisfactory machining accuracy can be achieved on the part. According to the index depth ap, it can be seen that to reduce the cutting force, ap<1mm must be made, which also shows that ultrasonic vibration turning is particularly suitable for precision and ultra-precision machining.
Features of Cake Printer :
1.Food Printer with edible ink can print on all kinds of food.Each item can be printed as a unique one with colorful photos
2.Easy operation, the computer connects with printer directly, user will get beautiful real image on cake without any professional skill.
3.We also can provide related edible printing material for you.
4.Wide application. This machine is suitable with cake, bread, biscuit, macarons...kinds of food.
5-35º
Name
Cake printer
Print head
DX5
Print size
21*38cm
Print color
CMYK+LC LM
Print speed
A4 photo/163s
Printing resolution
5760*1440dpi
Nozzles
90*6=540
Interface
USB 2.0
Net weight/Gross weight
35kg/42kg
Printer size
57*48*44cm
Height adjustment
Handle/Automatic
Working power
110-220 50-60Hz 30W
Operation system
Windows 2000/XP/WIN7/Vista etc.
Temperature
Cake Printer
Cake Printer,Popular Cake Printer,Diy Cake Printer,Edible Cake Printer,A3 Cake Printer
Shenzhen Refinecolor Technology Co., LTD. , https://www.szuvflatbedprinter.com