Entry 5 + Practical 3

BLOG 5 + PRACTICAL 3

We are finally about to finish up with the product design stages!

WOWWW, how time has passed since finishing the first 3 steps in the process, we are now on to the 4th and final step in the chemical product design process, Prototyping and Product Development.

A quick recap on the 4 stages 😎:

1. Needs Identification
2. Ideation
3. Selection
4. Prototyping and Product Development (your location now 👽💨)

In this topic, we are learning all about materials, materials, materials. 

Although materials might be a commonly underlooked concept in the real world, a wise selection and consideration could make or break a design, and the reverse is true. (HEHEHEHA)

There are 3 parts to Materials Study.

1. Materials for Design (MFD) - selection of a material that is appropriate for the preconceived design of a product                                                                                                    
2. Design for Materials (DFM) - creating a product design that accommodates a material used (e.g. hairdryer's shell was changed from metal to plastic, however some changes to its design had to be employed for plastic to work with it.                                                          
3. Sustainable Design 🍃 - choosing a material that is sustainable in terms of economy, society and the environment

In this entry, I will be covering the Material Selection Process, Design for Materials, Suggestions for a Sustainable Design and the Practical 3 study and experiment on Material Properties (NOT TO MISS).

Materials For Design (MFD)

This essentially means making an appropriate selection of a material to be used in a product's design. This is known as Material Selection.

 For this, there are many factors to consider and evaluate to make an informed decision to select the most suitable material for a design. 

Doing so will not only allow a product to fulfil its intended function but also have a competitive chance in an economic sense by having the lowest cost and manufacturability.

There are 2 categories to consider in the Material Selection Process.

1. Physical Properties

2. Economical Properties

Some examples of Physical Properties of a material

- Surface Tension of Liquid

- Thermal conductivity of a Solid

- Viscosity of a Liquid

- Young's Modulus (Elasticity)

- Density 

- Boiling Point

You may now be flustered and thinking, wow this is SOOOOO complicated. Well, fret not!

With just 4 STEPS, you will be able to select the best material for YOUR Product.

In this activity, my team was tasked to select the best material for a disposable water bottle that does minimal environmental harm.

Before diving into selecting the material (hold ur horses 🐴🏇🏇), one should specify the characteristics required for the material to work.🌟🌟

Step One:

Specify Material requirements for the intended design.

Use the Acronym, FCO (Function, Constraints, Objectives)

You can see this as the Foundation and hence the most IMPORTANT in the process.

Step Two:

In selecting a material, we could use the COWS Matrix as an aid for us.

C - Criteria specified

O - Options of materials

W - Weightage of Options in percentages

S - Scoring

My team realised that polymeric plastic materials were the most versatile in terms of selecting a material that fit the FCO requirements. 

Hence, we diverted research towards that category of materials (Polymers) instead of metals, ceramics and composites.

This table uses COWS Matrix concerning the material properties that my team valued based on the FCO specified.  🐄🐄🐄

From this, you can see how valuable specifying the requirements intended before selecting a material is. 💭💭💭

Step Three:

Next, specify the reasoning behind the weightage of each criterion.

After Step Three, we have shortlisted the options to Polyethylene terephthalate (PET) and Polypropylene (PP). 🍼

Step Four:

COWS Matrix again, but this time for selection based on the economic properties; cost of material and machinability (ease of manufacturing). 🤑🤑🤑

And there you have it, 4 straightforward steps to aid in selecting a material for your design!

Now with this model, it becomes much easier and undeniable to select the best fit material for design. (pun intended)

Design for Materials (DFM)

In Topic 6, we learn about Design for Materials. This is the OPPOSITE of Materials for Design and it is an interesting concept to explore. DFM essentially means to modify a product's design to suit a material.

Here's an example to give a better understanding and appreciation towards DFM!

Hair Dryer:

• Outer Casing used to be made of Metal, which weighed about 1kg and would be very heavy and not user-friendly
• Design was subsequently modified whereby the inner elements are not in contact with the outer casing
• This allows for Plastic, which has a low melting point to be used without the heat from the elements to melt it

In Class, we were given an activity to do to increase our understanding of DFM Selection.

Step ONE:

Select a material that piques your interest.

So, my team went onto SP E-library (Chris Lefteri Design Library) to look at the wide array of materials that are available to select from.

We shortlisted the search to a rather unique material, "PORON" aka the Material that can do it all. 

A foam that offers long-lasting cushioning in a product over the span of its useful life.

Boasting lightweight, flexible and a breathable layer that draws water vapour and perspiration away from its surface. This high-density material has been used in a wide variety of applications from mouse pad surfaces to shoe insoles and even sock liners to protective equipment for athletes. Lastly, this material can be custom formulated for the needs of a specific product manufacturer's physical and aesthetic requirements, with concern to its firmness and density.

Step TWO:

Think about HOW this material can fit into a new design or if there are any modifications to a current design that can be made to fit the material.

This is what my Team came up with...

This idea is great as a replacement for helmet cushioning where it can serve the user for better comfort - wick sweat and support the user's head. 

(Selecting a design for a material) 

Side note: I feel that this should be used in our DCHE Lab (ECTC) Helmets so that we do not feel so Hot and Stuffy all the time while wearing full PPE 🤣.

 

My Classmates and I having to do housekeeping in full PPE 😭😭

However, on a serious note, the material is rather costly. Hence it is best used in custom designs.

Another great way to capitalise on the benefits of this material is for the inner layer lining of phone cases to enhance the protection of the phone case as a shock absorber. 

(Modify the Design to allow the material to be used)

Sustainable Design🍃🍀

So, what does sustainable design mean anyway?

Sustainable Design is an approach to creating products and services that consider the social, economic and environmental impacts throughout the phase of a material's initial usage up to its end of life.

Last but not least, for the class activity, we were tasked to make changes to the design of our product to make it more environmentally sustainable.

Chemical Product at hand is our Water-Cooled Headphones!!

Based of from discussions in Term 1, my team first decided to look for a SUSTAINABLE alternative as a replacement for the materials used. 

For the Materials used, Cotton fabric was the original material that was selected for the headphones' ear muff cover. 

However, it is not sustainable as it requires high amounts of embodied water to produce.

Embodied water refers to the amount of water required to produce just 1kg of material.

For Cotton, the embodied water is about 10,000 Litres! Can you believe it? 

Well neither can I...

Hence, this re-emphasises the importance of Sustainability in Product Designs.

Next, we also considered the process loop for this system; the fluid cooling system. We decided that we could look into a SUSTAINABLE alternative coolant instead of water.

Click here to view my team's Sustainable Design document, with more information available ;)

Practical 3: Material Properties

Here's a quick overview!

This practical session was fun and "sus" at the same time.

If u get it u get it haha 😜 

Sus...

Reference to the Imposter Sus Meme

In Practical 3, my team completed an experiment to find out the Viscosity of an unknown liquid solution...

A quick recap, Viscosity refers to a fluid's ability to resist flow or deformation.

Here's a pic of me holding my prized possession...

To find the viscosity, we used the traditional; Flow Cup Method.

Close-up of how the flow cup looks like

The flow cup is a small container that acts as a gradual funnel with a small hole at its bottom. Fun fact! Did you also know that the flow cup can be 3D Printed? Upon my further inspection at the lab, I realised that the flow cup was just a simple structure that showed 3D Printed Consistencies 🤣🤣 (#Themoreyouknow)

Some given information:

• The viscosity of 2 varying solutions (21cP and 3cP; where cP is a unit of viscosity)
• Linear relationship of the 3 solutions, hence a graph of y = mx + c can be plotted
• Time taken for fluid to flow is an important parameter to be measured

Schematic of the Experimental Setup

This is a video of the experiment in play

So you might be thinking, HOW do we find the viscosity of the unknown solution with this experiment?

Honestly, this experiment is much easier than it looks!

First, my team began to record the readings of the solutions for a set of 4 runs each.

When in Rome...

Readings of the experiment

By analysis of the results, the unknown solution has an average flow time between that of both the standard solutions. Hence, the viscosity of the unknown solution has to be between that of both the standard solutions as well!

From this, it became obvious that the graph relationship to plot was a viscosity to time graph. 

I got to work immediately and capitalised on the Excel skills I attained while being a volunteer helper for the Annual Excel Day for DCHE Students. 💡(Eureka Moment)

Documentation of the process in Excel...

By using Excel to plot results on a graph, the equation of the graph can be established with minimal work by the user.

y = Viscosity of solution

x = Time taken for fluid to flow

By substituting the x for the unknown solution, y of the unknown solution can be found.

The viscosity determined was 3.22cP. 

To make sense of this result, the flow time for the unknown solution (16.308s) was much closer to that of Standard #2 (3cP, 16.190s) and further away from 

Standard #1 (21cP, 25.715s). Hence we know that our result is logical 😄😁👍

A reflection of this experiment...

This experiment was fun and enriching for me. 

The viscosity of a fluid is a physical property that is important in industries such as Food or Production; where viscosity determines a fluid's workability with a process/pump/pipes. 

One limitation of this experiment was that it was conducted solely by human hands and did not utilise machines; which are obviously more accurate.

Nonetheless, it is spectacular to experience that we can determine an unknown parameter with the usage of physics and mathematics together with the right information. This is truly the embodiment and marvel of the engineering mindset and reach!

Now, for some behind-the-scenes!

That will be all for this Entry!