GEA's Global HVAC Technology Blog Blog

GEA's Global HVAC Technology Blog

GEA's Global HVAC Technology Blog covers a range of topics including:

  • Core HVAC Technologies
  • Technology & Patent Evaluation
  • Manufacturing Technologies
  • Product Quality Improvement
  • Materials/Failures/Corrosion
  • Product/Technology Commercialization
  • Business Strategy Development
  • New Factory Design & Equipment

We'll draw upon our range of experts to provide comments, insights, technical articles and a little humor from time to time

We encourage your participation and feedback!

Previous in Blog: The Fourth Dimension in Material Selection   Next in Blog: Technology Roadmap for Energy Efficient Buildings
Close
Close
Close
5 comments

Material Selection: The Times, They Are A-Changing

Posted August 10, 2011 4:55 PM by geanorm

Editor's Note: CR4 would like to thank PJ Sikorsky for contributing this blog entry, which complements his last post about material selection.

Continuing the investigation of common materials selection issues, let's discuss the importance of regularly reviewing material selections. Things change! The graph below shows changes in the relative cost of aluminum, copper and zinc over the past 10-15 years on a per pound basis. (The costs are normalized to the cost of aluminum on August 1, 1998 which was about $1400 / tonne.)

All three of these metals are often used in applications where corrosion resistance to water is important. There are a whole host of factors which need to be considered when selecting the "right" material. Strength, density, resistance to specific contaminants, etc., all can influence a material choice, but cost is obviously an important parameter. If in 1998 our analysis showed that copper was the right choice for a given application when it was on cost parity with aluminum and zinc, is it still the right choice in 2011 when the price of copper has risen four times as rapidly as the cost of the other two metals?

Cost, obviously, is not the only thing that changes with time. Technology changes, too. New materials are being commercialized daily. Originally, charred oak was the material of choice for plain bearing applications. Have you seen many wooden bearings lately? Of course not, but we still do see a lot of lead-tin, or antimony-tin Babbitt bearings. Are these the right materials when metal matrix composite bearings are stronger, lighter, and often more cost effective? They may or may not be the right choice today, but we can't know without doing the analysis.

New technology in manufacturing is allowing us to use "old" materials in new ways. For example, for many, many years gray cast iron was not used in some bearing and sealing applications because it was not possible to obtain the required surface finish. But as machining technology improved, it became possible to utilize this old, inexpensive material in new applications.

Clearly, the point is that the materials world changes. The material we chose for a given application years ago, may not only be sub-optimum today, it may be absolutely wrong and we may be letting our competition get an unnecessary advantage in the marketplace if they are more nimble than we are at changing materials as the times change. If we only consider new or alternative materials when we design new equipment, we're missing out on opportunities to reduce cost, improve profitability and solve technical problems on existing equipment.

- PJ Sikorsky

Reply

Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.
Guru
Panama - Member - New Member Hobbies - CNC - New Member Engineering Fields - Marine Engineering - New Member Engineering Fields - Retired Engineers / Mentors - New Member

Join Date: Dec 2006
Location: Panama
Posts: 4273
Good Answers: 213
#1

Re: Material Selection: The Times, They Are A-Changing

08/10/2011 11:03 PM

I would really like to see nickel added to your price comparisons...

Reply
Commentator

Join Date: Dec 2010
Posts: 55
Good Answers: 1
#2
In reply to #1

Re: Material Selection: The Times, They Are A-Changing

08/11/2011 9:11 AM

thank you cwarner7 11,

Here is the chart with zinc added.

PJ Sikowsky

Reply
Guru
Panama - Member - New Member Hobbies - CNC - New Member Engineering Fields - Marine Engineering - New Member Engineering Fields - Retired Engineers / Mentors - New Member

Join Date: Dec 2006
Location: Panama
Posts: 4273
Good Answers: 213
#3
In reply to #2

Re: Material Selection: The Times, They Are A-Changing

08/11/2011 10:12 AM

Thanks, but...

Not encouraging, I am afraid...

The question arises because I have always preferred high-nickel compounds for corrosive environments...

Looks like I may have to go back to copper...

Reply
Member

Join Date: Aug 2011
Posts: 8
#4
In reply to #3

Re: Material Selection: The Times, They Are A-Changing

08/11/2011 11:25 AM

This just points to the importance of selecting materials very carefully and reviewing those selections regularly - nickel containing alloys are still appropriate for many applications, but we need to assure we're only using them where necessary. Historically it's been common for manufacturers to select a few 'favorite' materials and apply them universally. While this worked moderately well when material prices were stable and there weren't a lot of readily available alternatives anyway; it always did result in leaving some money on the table. The amount of money left on the table with this approach now is growing and I believe unnecessary.

Reply
Member

Join Date: Jan 2013
Posts: 9
#5
In reply to #2

Re: Material Selection: The Times, They Are A-Changing

02/04/2013 5:30 AM

a chart is a chart, like a sunrise in the ahead.

Reply
Reply to Blog Entry 5 comments
Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.
Copy to Clipboard

Users who posted comments:

catisred (1); cwarner7_11 (2); geanorm (1); psikorsky (1)

Previous in Blog: The Fourth Dimension in Material Selection   Next in Blog: Technology Roadmap for Energy Efficient Buildings

Advertisement