Chapter Subject What In lecture
2 Materials all 2
3 Processes for §3.1 up to and including 3
shapeless materials §3.9 and §3.15
4 Forming all 4
Important formulas:
Formulas related to stress-strain curve (Ch 2)
Normal anisotropy (Ch 2)
Planar anisotropy (Ch 2)
Drawing ratio (Ch 4)
Taylor’s formula (Ch 5)
Turning, drilling and milling formulas (Ch 5)
Punch force (Ch 7)
,All the important formula’s
Chapter 2:
Engineering stress: Engineering strain: Hooke’s law:
F: Force applied; A: cross sectional area L: elongation; L0: Starting length E: modulus of elasticity
Tensile strength: Rm = (Fmax/A0) elongation at fracture: δ = ((lmax – l0) / l0)x 100% True stress σw =
True strain εw = The flow stress: σv = C x (εw)n
( σ 1−σ 2 )2 + ( σ 2−σ 3 )2+ ( σ 3−σ 1 )2 dεw
Effective stress:
=
√ 2
Strain rate: ε(dot on top) =
dt
b
ln ( )
ε w , trans b0
anisotropy factor Rα = =
ε w , thick s
ln ( )
s0
R 0+2∗R 45+ R 90
normal anisotropy Rn =
4
, Chapter 1: Introduction
See slides tutorial 5 for the factors that determine the production choices.
The manufacturing processes can be split up in the following 6 main groups:
1. Primary shaping
2. Material forming
3. Dividing and material removal
4. Joining
5. Modification of material properties
6. Coating
Primary shaping
The most important processes in this category are those which convert shapeless materials into a clearly defined shape.
Material forming
Relies on the ability of materials to undergo permanent deformation under the influence of forces. Forming can be divided
in Bulk deformation and the forming of sheet metal. Bulk may involve subjecting the material to major changes of shape in
all directions. Sheet metal deformation perpendicular to the plane of the sheets are less importance.
Dividing and material removal
During these machining operations the cohesion of the initial material is broken. As a rule the superfluous (overbodig)
material as such during the dividing process. In the process of material removal the superfluous material is finely
distributed or even chemically bound, so that no usable material remains. Shape is obtained by movement of a universal
tool.
Joining
Components are assembled into one rigid whole. Roughly, the joining techniques can be classified in 5 groups:
1. Pin hole connections.
2. Joints that come about by bringing the material of the components to the melting point.
3. Joints using an intermediate layer.
4. Forming joints where the joining is accomplished by the forming of one or more components.
5. Joints by elastic deformation.
Modification of material properties
Modification of material properties relates primarily to the thermal treatment of metals. The modifications can concern the
volume of the workpiece, called bulk treatment, or a thin layer on the surface of the workpiece, called surface treatment.
The properties are modified to obtain the desired properties of the end product, or/and to be able to manufacture the
product better.
Coating
A large variety of coating techniques exist. They can be distinguished according to: (not necessary to know)
- Function (improvement of durability, embellishment)
- Applied materials (organic, metallic, ceramic)
- Applied processes (chemical, electrochemical, physical)