The Board of c: The author also wishes to express his deep gratitude to Dr. Mahiuddm Ahmed, Associate Professor, Department of Industrial and Production Engineering, Bangladesh University of Englllccring and Technology, Dhaka, for ab'Tt:eing to act as one of the external members step. of the examination board. It consists of a part of the metal being machined \half is heavily dcfomlcd, stagnant on the tool face and frequently sticks to the tool. CHAPTER-ONE Thinning edge; The cutting edges are formed by the intersections of the face and the flanks. The basic level and the level of the cuI, have been established for the determination of the. It is the angle bctm'en the projection of the side cut on the basic plane and the direction of feed. The angle of the final cutting edge is the bet angle\vecn the projection of the final cutting edge on the base plane and dlTection offccd (Figure i.4). It is the angle between the projections of the cut edges on the meeting plane (Figure 1.4). CHAPTER-TWO The shape and structure of the buildings are not stable and constantly change during the cutting process. The three main principles of experimental design are replication, randomization, and blocking. By replication we mean a repetition of the basic application. By randomization we mean that both the assignment of the experimental material and the order in which the individual runs or trials of the experiment are to be performed are determined randomly. A block is a portion of the experimental material that should be more homogeneous than the entire batch of material. Many of the early applications of experimental design methods were in agricultural and ecological science, and much of the field's thermology derives from this legacy. Most often, the mean or standard deviation (or both) of the measured characteristic will be the response variable. A successful experiment requires knowledge of the important factors, the range over which these factors should be varied, the appropriate number of levels to use, and the appropriate units of measurement for these variables. Many publications involve the study of the effects of two or more factors. In general, factorial designs are best suited for these types of experiments. By a factorial design we mean that each complete trial or repetition of the experiment examines all possible combinations of the levels of the factors. The effect of a factor is defined as the change in response caused by a change at the level of the factor. In some experiments we often find that the response at the levels of one factor is not the same at all levels of the other factors. The 2K design is especially useful in the early stages of experimental work, where many factors are likely to be explored. In most RSM problems, the form of the relationship between the response and the independent vanahles is unknown. If the response is well modeled by a linear function of the dependent variables, then the approximating function is the first-order model. An experiment design approach was then taken and a mathematical model was developed using the results. The developed mathematical model would serve to express the interactive effect of the two cutting tool variables on the BUE. Lathe machinc(onc). By using a grinding machine the rake and cutting angles of the tt)ol were changed and it was possible to maintain the accuracy of the angles within:t]0'. But with these two chosen ponies, it was not possible to directly obtain a practically feasible value of the maximum pitch angle. In RSM coded interchangeable arcs, extreme values of plus/minus unity must be assumed But even cosine transformation of pitch angles could not achieve unity. 11 it was therefore necessary to make a tnal and error to select both the constant to be added with the angle and the maximum value of the angle of inclination so that the second coded value could take the extreme values of pluslrnltlus unit. The response plate method is used to model and analyze the present problem, where the response of interest is affected by the main sidecut angle (q>l and pitch angle (y), and the objective is to optimize the response, i.e., the height of the BUE. Contour of the response area is drawn on an arc and lines of constant response are drawn in the X and Y planes. Analysis of the residuals from the regression model is required to determine the adequacy of the least squares fit. Any structure in such a plot would indicate that the model could be improved by adding the factor. Of course, we would like to know whether the order of the model pre-assumed is correct. The interaction of the factors presented in figure 3.2 with the data of table 3.3 and the convention sib'll oftahlc 3.4. Initially, the expenditure was carried out to observe the selection of a single parameter of the cutting tool at the height of BUE Thursday with a particular angle of beat, the angle of lateral withdrawal was changed and its erteCi was observed, Similarly for an angle particular sidecut, the angle of the rocket was also changed within a range and the quoted value of BUE was observed. But with these experiments it is not possible to evaluate the interactive elTect of paramctcrs mput. This chapter deals, firstly, with the eftcet of a single parameter (sidecut angle, angle) on the height of the BUE, followed by the analysis of the model performed by the response surface methodology and finally some features observed due to the change of ioh diameter. The effect of two individual geornelr tool parameters).-side euttmg angle and rakt' angle on 13UE height was observed non-independently and presented in the following secllons. It is observed that there is no trend of lateral cutting angle on ILJE. When the slope angle is in the lower range (i.e. y - -]" or -:i"), there are all the benefits. .: in the height of llUE With the increase of the side cutting angle or the pulling force. For different conditions of !p, effect of slope angle on height. in general, the height of the SUE decreases with a small increase in the slope angle of -5". After this, hcigh1 of RUE decreases continuously until 00 and the minimum at On From DOto +5\1 the height of 13UF- m increases The height of RUE decreases continuously from y = 100 to 00 and is minimal, it is 0° and then increases. In the course of the experimentation it was observed that for the same tool gcommodation and cutting conditions BUE were different. The height of BUE was found greater in the experiments of the later stage (Flgurc 4.5-4.8). It was,ccn that the height of 13UE increases from (~- 50 to 150 and then sharply decreases from ljI amllhen decreases continuously By analyzing the new experiments It IS clear that the height or BUE ISgrcatcr in new cases_. It is clear that height of BUE is higher in every case of new experiments_. Now for '{= _30 the height of BUE decreases gradually_ compared to new experiments ;1 IS observed that the height of BUE is higher new ease than the previous experiments. For a certain value of the bevel angle, if the primary side crop angle increases, the height of the RUE decreases, and this continues from y =.200 to +200. After this with. On the contrary, when the same operation was performed on the same solid work in the same condition at the inner surface, it was observed that the height of FLUE was higher in this case comparing 10 outer surface, ductility mcrcases from outcr surface to incr surface and grain size was also largcr inner surface then ltl oulcr SUrf3cedue to he3t trcalmcnt. CHAPTER-FIVE Ii) It can be concluded that both the inclined and the main side cutting angle of the single pomt euttmg tool affect the HUE height, leaving the possibility of optimizing the tool geometry in the context of the design of the embedded cdgc. In addition, the interactive ctTeet of both tool geometry parameters was observed in the design of the embedded edge. ii). For a specific value of the tool rake angle (1'), the highest value of BUE(h) was observed with the change of the main standard cutting angle (q), within the range of cost values, the same trend was observed in contrast to follow for any other values of the rake angle. It was observed that for a given set condition and using the same tool geometry, there was a deviation of 10 SUE height. In the later experiment, the BUE height was higher. This deviation could occur due to the variation in mechanical properties of the inner and outer regions of the work material. Higher ductility and lower hardness of the internal part of CVlindrieal resin material could be attributed to developing higher I3UE height. 5.2RITOMMF,NPATIONS FOR }'lJ'nJRl: WORK. By only changing the tool geometry, complete prevention of the 3IJE formation in turning machining may not be possible. Some recommendations for further studies are given:. i) Similar experiments can be carried out considering other factors such as ejection rate, depth of cut, cutting tool tip radius, etc. ii). RSM can be used with a larger number of variables to determine the interactive effect. iii) Deburring can be done with a higher rake angle and a lower main side angle of the cutting tool and vice versa. APr"-:NDlX-A Appendix-A: Experimental data 17, SlImil Kanti Sikdar "A study on kinkmatic geometrical parameters of a 1001, its wear and work surface finish during up and down milling", M.Engg, ThesIs I.P.E.INTRODllCTION
RACKGROlJND STUDY
CHAPTER-THREE
CHAPTER-FOUR
Conclusions and Recommendations
EFFECT OF TOOL GEOMETRY ON BUILT-UP-EDGE FORMATION
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