Optimized Engineering Materials Through Cleantech

How do we arrive at selecting a material for a particular application? There are so many materials available today that the Designer (although has excellent material systems at his disposal) would be pitted against a plethora of materials. This makes it difficult to arrive at optimum selection. The first requirement in any Engineering material is that the said material should have certain basic mechanical characteristics such as strength and rigidity. There are many other characteristics such as water effect, chemicals effect, environmental effects (both during manufacture and "in-use"), sunlight effect, wind effect, effect due to sea, temperature effect, electrical effects ... and many more such characteristics. The following tables help us to understand certain basic mechanical engineering properties of some materials that are generally used in various current applications:

TABLE-1

TABLE-2

[Note: The Properties presented here are based on various Literature data]

In present day world, we have come to recognize that atmospheric carbon increase is one of the biggest challenges that any designer, technologist and materials specifier has to overcome, before zeroing-in on any engineering material. And, in this, we have to look at the Life Cycle Analysis (LCA) of the said material from cradle to cemetery ... and back again ... It is in this context that we had recently zeroed-in on a specialty material formulation and Composite design, which is being experimented for the design and Construction of Sea-worthy Fishing Boats. The current materials used are: Special wood, Fiberglass-Polyester, and Steel. The Indian fisher-folks prefer wood based construction to the other materials.

Our task was to arrive at an appropriate "substitute" that would not only replace all of these but also do minimum harm to the environment ... apart from looking at the most important requirements of easy availability and economics of operation/ maintenance (including high durability). After careful observations, study, analyses and experimentation we zeroed-in on two Vegetation based Renewable Resources (RR):

BAMBOO and PALMYRA TREE RESOURCES

BAMBOO CLUSTER

PALMYRA TREE

Both the above Tree/ Vegetation species are abundant in India and in most tropical nations. However, hitherto there has never been any attempt to look at these "simple" vegetation resources as competitors to even the "strong" engineering material, Steel! But then, our attempt here is to present the concept that these Vegetation Resources could soon outwit almost any sophisticated engineering materials (including Ultra-high strength steels, Carbon Fibers, and "Kevlar").

The "trick" is in modifying and engineering these simpletons into specialty engineered systems ... within the scope of CLEANTECH definition. This would create the foundation for Optimized Engineering Materials Formulations/ Specifications

... More later [Note: If any technical person has some questions to ask or other technical experiences to be presented, the writer wishes to know about them. Please don not hesitate to ask/ tell]

AN IN-SITU HYBRID HAND-MOLDING FOR OPTIMUM ENGINEERING

Let us look at the following photo sequence that shows an innovative hybridization of split bamboo material being converted into a sea-worthy dinghy:

1.

BOAT/ DINGHY TEMPLATE

2.

SPLIT BAMBOO WEAVING AROUND THE TEMPLATE

3.

TOTAL WOVEN DINGHY SHAPE AROUND THE BOAT-TEMPLATE

4.

WOVEN BAMBOO DINGHY REMOVED & OUTER LAYER CONVERTED INTO HIGH-STRENGTH COMPOSITE

5.

THE RIMMED AND RIBBED HYBRID BAMBOO SYSTEM DINGHY

6.

THE HULL BEING TESTED FOR BUOYANCY AND STABILITY

7.

THE COMPLETED DINGHY BEFORE ENGINE MOUNTING

8.

THE MAIDEN SEA-RUN WITH A NEAR VERTICAL JUMP OVER INCOMING TIDE

The Dinghy in "question" was designed, fabricated and test run under a Project that was completed in a record time of three months (from start). The works included raw-materials study and selection; raw materials procurement; designing the "formulations" for material systems; designing the composites involved; designing the production methods; practical fabrication with an eye on "quality" control ... many of these involved extremely difficult choices and also there arose necessity to innovate in various ways

The following Raw-materials were used:

1. Bamboo

2. Palmyra Palm Tree Fibers

3. Locally available mineral systems

4. Epoxy resin + Polyamide Curing Resin

5. Glass fiber Chopped Strand Mat for hybridization

6. Titanium Di Oxide and a few other Chemicals for UV resistance

In order that we are able to understand the optimization in engineering properties, the following are compared:

(i) Specific Weights: Steel = 7, 850; Fiber-glass composite = 1, 660; Boat quality Wood = 600; Hybrid Bamboo Composite = 920 (the units are in Kg/ m³)

(ii) Sp. Tensile Strength [Tensile strength/ Sp.wt]: Steel = 5350; Fiber-glass Composite = 18, 072; Wood = 10, 000; Hybrid Bamboo Composite = 7, 065 (the units are in meters)

(iii) Rigidity Modulus [This would be explained later]: Steel = 17.5; Fiber-glass = 220.32; Wood = 2239.52; Hybrid Bamboo Composite = 1345.98 (the units are in Kg-m²)

.... We shall discuss these in more detail later

(PLEASE NOTE: The different Composite Systems and Technologies are Under Patent Application]

Please send bamboo! (it is very expensive here in Canada!)

Perhaps the Genetic Scientists can create some "Northern Bamboo" for Canada, Russia, etc...

Hi chrisg288

Bamboo is available in plenty in almost 70% of the tropics, where there are about 160 nations. And almost next to nothing has been done to consider this wonderful resource as an Engineering Material. The average tensile strength of split-Bamboo fibers range from about 250 MPa to over 500 Mpa. The sp.gr of bamboo averages to about 0.38 to 0.4 (that of Low carbon steel is 7.85). Thus, on a weight-to-weight basis (based on optimum design), bamboo is over 20 times stronger than low carbon steel!

The Illustration indicates the Tropical belt..that lies between 23.5 deg N and 23.5 deg S across the Equator, where bamboo is available. These are Not available in Temperate Zones such as Canada, Russia and other such nations that lie above this belt

Another factor to be noted is that countries such as India have specific "communities" who work ONLY on Bamboo or other Reeds ... (for example the YERUKALA Community in Southern India). These people are highly skilled and have traditional bamboo weaving methods passed on through centuries. There are also other such Basket weaving Community in India (Medaris)

Please note: Our Project has Twin aims: (1) To Create Alternate Engineering Substitutes; (2) To support the downtrodden communities who are involved in Bamboo basket weaving for centuries... but without any real development

Can you cook it, and break it down to fibres?

then you can make paper, fibreboard, chip board, etc... admittedly with some more advanced technologies to processes it... but what kind of materials can be made with it? can it be an export product?

It is expensive here, but if industrial nations could use it as a raw resource, then those who harvest it and prep it for shipment could profit.

Are there any medicinal ingredients, oils, etc. available in these materials?

thanks,

Chris

India's paper were manufactured using bamboo, until about a decade and a half ago. But, in view of the dwindling resources situation the Government banned usage of bamboo for paper. As noted by you, there were other uses too: Fiber Boards and Chip Boards. Further, bamboo has been categorized under "classified" material, controlled by Government arrangement, under Bamboo Corporations in each state, strictly monitored by the Ministry of Environment and Forests (Gvt. of India). An example of such a Corporation is in the southern most Indian state, where much Industrial work has been done and is continuing (although at very slow pace) ... Kerala Govt. Bamboo Development. More details on India's development works could be noted in the same website

However, as those are under Government control, progress is slow and new technologies are not available to entrepreneurs.

Visit the following sites:

http://www.greenlivingtips.com/articles/191/1/Uses-of-Bamboo.html

http://lifestyle.iloveindia.com/lounge/medicinal-properties-of-bamboo-shoots-9756.html

http://www.thaitable.com/thai/ingredient/bamboo-shoots

great stuff.

I'm confused about the political controls... are you saying private use of bamboo is proscribed or prohibited?

chris

Private uses are not prohibited; but using Bamboo by the giant corporations for Paper and related products has been banned. This is to support the smaller communities and also to control indiscriminate "forest felling" ... bamboo is currently a Forest grown specie. However, there is tremendous scope for new technology developments and business generation.

My attempt is to initiate some technology/ Product developments that would take bamboo to the "high end" engineering levels. The current Boat building Technology is a beginning

What is the a common "Large Diameter" pipe shape that bamboo can produce?

Derived Properties that Help in Materials Selection

The initial selection of appropriate engineering materials for particular type of application is not based on mere Tensile Strength and Elastic Modulus. If that were so, very few engineering materials would compete with Steel. The following Derived Engineering Properties may be noted:

1. Specific Tensile Strength: This is mathematically derived as:

Tensile Strength/ Sp wt (Unit = Meter)

In conceptual terms this could be viewed as the Length of any Material that hangs on a ceiling and the resultant weight creates sufficient stress at the "anchor" point to effect "Breaking Load" by its own weight. The cross section being unity

2. Equivalent Weight Section: This is mathematically derived as the Section depth of a rectangular beam having unit width in cross section, wherein the resultant cross section x unit length (volume) has the same weight of low Carbon Steel beam with unit width. Its unit is in cm

(Schematic ... Not to Scale)

3. Equivalent Weight Rigidity factor: This is mathematically the multiplication of Elastic Modulus of the material in question by the Moment of Inertia of the Rectangular beam cross section as in 2 above. Its unit would be in Kg-M²

Let us look at some Derived Engineering properties of a few Composite materials

[NOTE: 1. Hybrid Bamboo¹ comprises Bamboo 30% Kevlar49 10%; Hybrid Bamboo² comprises Bamboo 30% Carbon Fiber 10%; The different properties are based on estimations using available data, and are only for comparative study.]

It would be noted that Composites based on Bamboo could be strong contenders to compete with even specialty (exotic) Engineering Composites consisting of "KEVLAR-49" and Carbon Fiber

Comparative Design Advantage of Bamboo based Composites

In order that we are able to arrive at "optimum" engineered material system for a particular design need, we shall compare the "Rigidity factors" of various Composites with respect to that of Low Carbon Steel (which is the standard structural engineering material)

The average thickness of Steel sheet material needed for the hull of a 20 ft Dinghy that needs to be "seaworthy" is estimated as 6 mm. The corresponding thickness factors and other derived properties for the Composites (based on equivalent Rigidity factor) are presented below:

It is noted that we could engineer superior structures using both 40% bamboo composite and bamboo-glass composites (30 + 10). The cost factors would be lesser than that of Low carbon steel structure, even at 50% excess thickness levels in the Bamboo composite structures. That would mean far superior Strength-Rigidity factors in the resultant engineered systems. See the Table below:

It is further noted that even at 50% extra over the "minimum thickness" for "steel equivalent" Rigidity factor, the weight factors are about one-fourth of steel … allowing us to have greater Strength-Rigidity-Economics. We may also note the greater advantage of using Bamboo based Composites, compared to "superior" engineered composites in "KEVLAR-49"

SOME PRACTICAL ASPECTS OF HYBRID BAMBOO COMPOSITE CONSTRUCTION

Unlike advanced fibers that have been made into high quality and sophisticated weaves and mat systems, bamboo mat and woven systems are based on the specific skills of certain communities. Thus, were we to develop and fabricate high caliber products such as Boats or Auto body systems, Bamboo mat systems cannot be directly molded into shapes, as are done using Glass fibers and other high caliber fibers. The present development could be noted by studying the Photo illustrations below:

It would be observed that two types of skills are required to fabricate any end product (Boat in this case):

1. Bamboo weaving skill

2. Fiber Glass Molding/ Composites making skills

Bamboo weaving is done using "split" bamboo reeds. Here the boat shape is woven by skillfully weaving around a template:

In the ultimate analyses, we need to recognize that hybridized composite construction using bamboo split reeds has the following advantages:

1. Natural Renewable Resources (RR) are being used, resulting in "GREEN" Product

2. Local skills of traditional communities get enhanced economic value, resulting in huge benefits to the community and the society

3. Traditional skilled personnel do not have to look for "jobs" and living needs elsewhere, resulting in reduction in "shifting populations"

4. Overall weight reduction and materials usage reduction are involved

5. Strength-durability-economics factors are improved (please see the previous thread: http://cr4.globalspec.com/comment/752620/Re-Optimized-Engineering-Materials-Through-Cleantech)

6. Products would be environmentally benign

AN EXAMPLE OF DESIGN POSSIBILITIES USING BAMBOO COMPOSITES

It is observed (based on the different estimates and study of the strength-rigidity aspects of hybrid bamboo composites) that we could attempt MONOCOQUE designs of Automobile body and even Aircraft Fuselage

The illustration above indicates that we could attempt to design Monocoque systems for two of the main parts of Small Size Aircraft:

1. FUSELAGE

2. POWER PLANT SYSTEM COVERING

We are planning to design and fabricate a Light-weight Two-seat Aircraft as a first stage design/ development

We are looking for sponsorship of thees developments, which have great world-wide potentials

[Please Note: The different Bamboo/ Natural Fibers Composites developed so far are under Patent Applications]

... any one out there to support our works?