Results

Abaqus Grinding

Using the capability of the software to save in different formats, a drill was generated and exported into Abaqus and DEFORM using the SAT and STL formats, respectively. The drills were then meshed using the meshing module of these two packages. The resultant meshes along with the original solid model can be seen in Figure 4.14. Figure 4.14 Solid Model left , Meshed in Abaqus middle , and Meshed in DEFORM right . Figure 4.14 Solid Model left , Meshed in Abaqus middle , and Meshed in DEFORM...

Techniques to Quantify Edge Defects in FRP Machining

Measuring the defects around a hole edge during FRP machining is challenging due to several reasons, including the out-of-plane nature of the defects and because the brittle fibers break during measurement. Also, sometimes the defects themselves may not be of concern, but the debris they cause during assembly may be an issue. It is again instructive to draw comparisons between FRP drilling and metal drilling to better understand techniques for quantitative characterization as metrology and...

Finite Element Modeling

Metal Burr Formation After Drilling

Significant work has been done in modeling metal cutting using the finite element method. The earliest models such as those by Komvopolous amp Erpenbeck 10 and Strenkowski amp Carroll 11 defined a parting line to denote the region of chip separation. Huang amp Black 12 discussed several chip separation criteria classifying them broadly as geometric and physical, and suggest the best criteria to apply for accurate simulations. More sophisticated chip separation criteria employ continuous...

Drill Margin and Relief

Drill Margin Pictures

Existing literature does not extensively cover the modeling of the drill margin and relief, hence these features are only approximately drawn. In order to generate these features, we need to know the margin length and the relief width. Using this, a 2D cross-section is Figure 4.10 Solid Drill with both Flanks cut Figure 4.10 Solid Drill with both Flanks cut Figure 4.11 Drawing the Cross-section of the Margin and Lip Relief Cut Figure 4.11 Drawing the Cross-section of the Margin and Lip Relief...

Automated Drill Design Software

This section discusses the development of an automated drill modeling tool in Solidworks. The tool uses Solidworks to generate a 3D model of a drill based on manufacturing parameters of the drill supplied by the user. The need to use manufacturing parameters to model drills will be established. The applet uses a GUI to accept these parameters from the user and generates the model on-the-fly. The applet allows the user to save the model in a variety of formats which can be them imported into a...

Quantifying Edge Defects in FRP Drilling

This section of the report examines the imprecisions that are observed at the hole edge when drilling fiber reinforced polymers and presents an analytical model to quantitatively estimate them. The model predicts the defects by considering the incomplete cutting of the fiber in parts of the laminate that have already delaminated. Existing work on machining FRPs, specifically looking at drilling and drilling defects is first discussed. This is followed by a detailed discussion of the formulation...

What are FRP Composites

Particulate Composites

A composite material can be defined as a multiphase material with chemically dissimilar phases separated by a distinct interphase 1 . Composite materials are inherently anisotropic in the macroscale due to the multiple phases in many cases, the phases themselves are anisotropic and it is possible to design the materials with controlled anisotropy. This makes composites very useful in applications where specific engineering properties are needed in specific material orientations. Although...

Chapter Conclusions

As mentioned earlier in the Introduction, although these two projects seem unrelated, they contribute to solving the larger problem of developing a fully featured numerical model of FRP machining. The defect prediction model is a simple first-order relationship which relates defects observed during FRP drilling to material properties and process parameters. The model shows good qualitative agreement with experimental results. The model establishes high thrust forces as the main cause for these...

FRPs and the Aerospace Industry

Multilayer materials or stackups are used extensively in the construction of aerospace structural members. They provide increased strength-weight ratios compared to traditional structural material. Also, the different layers provide a wide range of functionality that increases the utility of the structural member. Composite materials are being used increasingly as constituents of these stackups. Typical aerospace panel stackups include CFRP CFRP CFRP - Carbon Fiber Reinforced Polymers , CFRP...

User Interface Development

Drill Solidworks

Visual Basics APIs was used to design an ergonomic and accessible user interface. The interface accepts inputs from the user regarding the geometric and manufacturing specifications of the drill in SI units. A schematic of a drill with all the dimensions marked is also shown alongside for ease-of-use. After entering the data, the user can click the Generate Drill in order to invoke the necessary Solidworks commands to execute the program. Following a brief wait, the drill is generated in...