From 80ec507c9bada6951e2a1837b14b32bda00f3e0a Mon Sep 17 00:00:00 2001
From: Alvie Rahman <alvierahman90@gmail.com>
Date: Mon, 11 Oct 2021 17:49:57 +0100
Subject: [PATCH] Complete MMME1029 Lecture 2

---
 mechanical/mmme1029_materials.md | 152 ++++++++++++++++++++++++++++++-
 1 file changed, 151 insertions(+), 1 deletion(-)

diff --git a/mechanical/mmme1029_materials.md b/mechanical/mmme1029_materials.md
index 4391e08..054c66b 100755
--- a/mechanical/mmme1029_materials.md
+++ b/mechanical/mmme1029_materials.md
@@ -62,7 +62,7 @@ work:
 
 2. What are the main classifications of materials?
 
-   > Metals, glass and ceramics, plastics, elastomers, 
+   > Metals, glass and ceramics, ~~plastics, elastomers,~~ polymers, composites, and semiconductors
 
 3. [There are] Few Iron Age artefacts left. Why?
 
@@ -104,3 +104,153 @@ work:
 2. What material properties were mentioned in the second slide set?
 
    > Young's modulus, specific heat, coefficient of thermal expansion
+
+# Lecture 2
+
+## Metals
+
+- Ductile (yields before fracture)
+- High UFS (Ultimate Fracture Stress) in tension and compression
+- Hard
+- Tough
+- High melting point
+- High electric and thermal conductivity
+
+## Ceramics and Glasses
+
+- Brittle --- elastic to failure, no yield
+- Hard (harder than metals)
+- Low UFS under tension
+- High UFS under compression
+- Not tough
+- High melting points
+- Do not burn as oxide ceramics are already oxides
+- Chemically resistant
+- Poor thermal and electric conductivity
+- Wide range of magnetic and dielectric behaviours
+
+## Polymers
+
+- Organic---as in organic chemistry (i.e. carbon based)
+- Ductile 
+- Low UFS in tension and compression
+- Not hard
+- Reasonably tough
+- Low threshold temperature to charring and combustion in air or pure oxygen
+- Low electrical and thermal conductivity
+
+  - There are some electrically conductive polymers 
+
+## Composites
+
+- Composed of 2 or more materials on any scale from atomic to mm scale to produce properties that
+  cannot be obtained in a single material
+
+  - Larger scale mixes of materials may be called 'multimaterial'
+
+- Material propertes depends on what its made of
+
+## Organic vs Inorganic Materials
+
+- Organic materials are carbon based
+- From chemistry, organic compounds are ones with a C-H bond
+- Inorganic compounds do not contain the C-H bond
+
+## Crystalline vs Non-Crystalline Materials
+
+- Most things are crystalline
+
+  - Ice
+  - Sugar
+  - Salt
+  - Metals
+  - Ceramics
+
+- Glasses are non-crystalline
+## Material Density
+
+$$\rho = \frac m v$$
+
+- Density if quoted at STP (standard temperature and pressure---$298$ K and $1.013\times 10^5$ Pa)
+- Metals, ceramics, and glasses are high density materials
+- Polymers are low density
+- Composites span a wide range of density as it depends on the materials it is composed of
+
+  e.g. composites with a metal matrix will have a much higher density than those with a polymer
+  matrix
+
+## Material Melting Points
+
+- Measured at standard pressure and in an intert atmosphere (e.g. with Nitrogen, Argon, etc)
+
+  - Diamond and graphite will survive up to 4000 \textdegree{}C in an inert atmosphere but would
+    burn at around 1000 \textdegree{}C in oxygen
+
+- High melting points -> high chemical bond strength
+
+## Material Corrosion
+
+- It's not just metals that corrode
+
+- Polymers
+
+  - UV degradation
+  - Water absorption can occur in degraded polymers
+
+- Glass
+
+  - Leaching
+  - Sodium ions can leave the glass when covered in water. If the water stays, the high pH water
+    can damage the class
+
+## Self Quiz
+
+### Consolidation Questions 1
+
+1. 
+
+   i. Metal
+   ii. Titanium
+
+2. 
+   i. Polymer
+   ii. Polyester
+
+3. 
+
+   i. Ceramic
+   ii. Alumino-silicate
+
+4. 
+
+   i. Composite
+   ii. GFRP or CFRP
+
+5. 
+
+   i. Metal
+   ii. Aluiminium alloy
+
+6.
+
+   i. Metal
+   ii. Aluiminium alloy
+
+7. 
+
+   i. Polymer
+   ii. Acrylic
+
+8.
+
+   i. Ceramimc
+   ii. Glass
+
+9.
+
+   i. Composite
+   ii. Concrete
+
+### Consolidation Questions 2
+
+> ~~C~~ B