Blog entry 5 (week 11+ week12)

Hello guys! 👋🏻 Its me insyirah and im back to share with you guys what i learned in week 11 and week 12 of introduction to chemical design✨. For this blog, I will be talking about materials🪵.

In Week 11, we learned Materials for design, how exciting is that 🤩. We drived into the world of materials. For a product to function as designed, the choice of materials is critical. Material selection is about finding a material that meets the needs of the product design, widely available, easy to work with and also economically viable. The list goes on, it is not easy. But with practice and experience, we will be able to make better decisions on what materials to use. Material selection process is neccesary to identify one or more materials with properties that satisfy the functional requirements of the product.

Why is selecting the correct material important?

Getting this selection right by selecting the optimal combination your design has enormous benefits to any engineering-based business. It leads to lower product costs, faster time-to-market, and a reduction in the number of in-service failures.

Materials properties:

It is categorised into:

• mechanical properties (eg. tensile strength, ductility, hardness, density)

• thermal properties (eg. thermal conductivity, specific heat capacity)

• magnetic properties

• fabrication properties (eg. ease of machining, availibility, ease of welding)

• environmental properties (eg.corrosion properties, polluting effect, toxic effects)

In order to select the best material for your design , you must

1. Define material requirement for design

2. Select and evaluate candidate materials (COWS)

3. Choose the most economical material

The basic question is how do we go about selecting a material for a given part?

This may seem like a very complicated process until we realize than we are often restrained by choices we have already made. For example, if different parts have to interact then material choice becomes limited. When we talk about choosing materials for a component, we take into account many different factors. These factors can be broken down into the following areas :

Material Properties	a.The expected level of performance from the material
.Material Cost and Availability	a.Material must be priced appropriately (not cheap but right) b.Material must be available (better to have multiple sources)
Processing	a.Must consider how to make the part, for example: Casting, Machining, Welding
Environment	a.The effect that the service environment has on the part b.The effect the part has on the environment c.The effect that processing has on the environm

After we have been taught with the knowledge about materials, me and my team was then tasked to select the most suitable material for the teat and cover of a polycarbonate baby milk bottle. Yay lets get to our group work!

CA2 REPORT PART 1

Step 1 : Material requirements

Function	It is typically used by infants and young children for feeding purposes.
Constrains	lightweight, non reactive to food ingredient, corrosion resistant
Objective	​Convenient

Step 2 : COWS matrix

for teat:

		Option 1	Option 2	Option 3
Criteria	Weightage	silicon	latex	​FDA neoprene
safe for consumptions	​50%	5 5(50%)= 250%	5 5(50%)= 250%	5 5(50%)= 250%
flexibility	30%	5 5(30%)= 150%	4 4(30%)= 120%	4 4(30%)= 120%
wear and tear	20%	1 1(20%)= 20%	2 2(20%)= 40%	3 3(20%)= 60%
total	100%	420%	​410%	430%

Step 3: Choosing the most economical material:

		Option 1	Option 2
criteria	weightage	Silicon	FDA neoprene
cost of material	60%	​cheap score: 5	cheap score: 5
ease of fabrication	40%	Good score: 4	​Medium score: 3
total	100%	460%	​420%

Based on this , the selected material is Silicon

That was it for materials for design, isn't interesting how much thought you have to put into just to create a product? Did you think i am done with my blog? Unfortunately no. The next part, i will be sharing with you guys on design for materials and sustainable design.

Design for materials:

In many instance, we want to use a certain material for a certain reason and because of that, we make changes and even compromises to the product design to accommodate the materials. These reasons can be cost, aesthetics and environmental sustainability. Finding a material with property attributes that meets or exceeds the requirement of a product and at the same time does not possess manufacturing difficulties and is not

exorbitant in price is a dream of many product design engineers.

Did you know that the first ever hair dryer was made in 1890? How cool is that, considering they do not have the technology we have in the current day! It was a large, seated version that consisted of a bonnet that attached to the chimney pipe of a gas stove. It could only be used by having the person sit underneath it and looked disarmingly similar to something out of a terrifying sci-fi movie. Oh the things we do in the pursuit of beauty!

Today, 2022, a hair dryer have developed so much. Committed to changing haircare forever and after years of development, our tight-knit team of entrepreneurs, designers and scientists have finally freed the hairdryer from the tyranny of clunky cords with the introduction of the world’s first cordless hair dryer.

Me and my team we the tasked to select ONE material that appeals to our group and discuss how this material can be used as a replacement to a material in an existing product without any significant changes in the design to enhance the functionality of an existing product through some changes in the design.

Sustainable design

In Lesson 5, the idea of Design for Material is introduced. It is about reviewing the chemical product design so that a particular material can be used. Sustainable design was also introduced. Sustainable design is the approach to creating products and services that have considered the environmental, social, and economic impacts from the initial phase through to the end of life.

Some Design Considerations/Principles:

• Use non-toxic, sustainably produced, or recycled materials.

• Use energy efficient processes.

• Make product last longer.

• Design for reuse and recycling. (e.g. easy to disassemble)

• Consider product life cycle.

• Shift from personal ownership to shared ownership.

• Buy from nearby