OT - What are you doing right now?

JohnInCarolina

Ozzie_Isaac said:

JohnInCarolina said:

kl8ton said:

JohnInCarolina said:

Plotting trajectories to strength surfaces, in principal stress space (projection onto sigma_3):



The green surface is our best guess of what the strength surface for this material could be.  The blue, red, and yellow lines correspond to an analysis of three different specimens of a notched Aluminum material.  The points where they end are where the specimens all failed.  The fact that they just touch the surface seems to indicate that failure is being governed by strength in this case, as opposed to energetics.   

What method is employed to cause failure?   Is this metal forming?  Metal cutting? Abrasive testing? Temperature testing?   Other?  I'm just curious as in my past, I did FEA on the feasibility of proposed tooling to produce automotive parts.  I'd evaluate. . . Er the computer would evaluate if a proposed forming process would result in product fracture or excessive thinning.  I enjoyed it.  

Here we are performing simple 3-point bend tests of beam-shaped specimens.  What we're doing is enhancing our understanding of crack nucleation vs propagation.  It turns out they seem to be governed by fairly different physics.  

We use FEA for the calculations, and compare results to experiments conducted at a lab in Tel Aviv.  I actually teach a couple of different graduate courses on linear and non-linear FEA here at Duke.  

Out of curiosity, how do you control the surface finish on your specimens?  You theoretical data matches the empirical data so closely, you must be doing a pretty spectacular job of controlling the variables, surface finish, in my mind, being one of the critical ones.

Well really the match here is a result of the fact that the problem is over-driven.  The notch creates a highly localized stress field.  

They may do something in the lab at Tel Aviv to polish the surface within the notch, I’m not sure.

nolaegghead

Ozzie_Isaac said:

JohnInCarolina said:

kl8ton said:

JohnInCarolina said:

Plotting trajectories to strength surfaces, in principal stress space (projection onto sigma_3):



The green surface is our best guess of what the strength surface for this material could be.  The blue, red, and yellow lines correspond to an analysis of three different specimens of a notched Aluminum material.  The points where they end are where the specimens all failed.  The fact that they just touch the surface seems to indicate that failure is being governed by strength in this case, as opposed to energetics.   

What method is employed to cause failure?   Is this metal forming?  Metal cutting? Abrasive testing? Temperature testing?   Other?  I'm just curious as in my past, I did FEA on the feasibility of proposed tooling to produce automotive parts.  I'd evaluate. . . Er the computer would evaluate if a proposed forming process would result in product fracture or excessive thinning.  I enjoyed it.  

Here we are performing simple 3-point bend tests of beam-shaped specimens.  What we're doing is enhancing our understanding of crack nucleation vs propagation.  It turns out they seem to be governed by fairly different physics.  

We use FEA for the calculations, and compare results to experiments conducted at a lab in Tel Aviv.  I actually teach a couple of different graduate courses on linear and non-linear FEA here at Duke.  

Out of curiosity, how do you control the surface finish on your specimens?  You theoretical data matches the empirical data so closely, you must be doing a pretty spectacular job of controlling the variables, surface finish, in my mind, being one of the critical ones.

Are you suggesting microvoid coalescencence is purely a function of crystaline structure abnormalities in non-amorphic solids?

nolaegghead

Because f*ck if I know.

lkapigian

Ozzie_Isaac said:

JohnInCarolina said:

kl8ton said:

JohnInCarolina said:

Plotting trajectories to strength surfaces, in principal stress space (projection onto sigma_3):



The green surface is our best guess of what the strength surface for this material could be.  The blue, red, and yellow lines correspond to an analysis of three different specimens of a notched Aluminum material.  The points where they end are where the specimens all failed.  The fact that they just touch the surface seems to indicate that failure is being governed by strength in this case, as opposed to energetics.   

What method is employed to cause failure?   Is this metal forming?  Metal cutting? Abrasive testing? Temperature testing?   Other?  I'm just curious as in my past, I did FEA on the feasibility of proposed tooling to produce automotive parts.  I'd evaluate. . . Er the computer would evaluate if a proposed forming process would result in product fracture or excessive thinning.  I enjoyed it.  

Here we are performing simple 3-point bend tests of beam-shaped specimens.  What we're doing is enhancing our understanding of crack nucleation vs propagation.  It turns out they seem to be governed by fairly different physics.  

We use FEA for the calculations, and compare results to experiments conducted at a lab in Tel Aviv.  I actually teach a couple of different graduate courses on linear and non-linear FEA here at Duke.  

Out of curiosity, how do you control the surface finish on your specimens?  You theoretical data matches the empirical data so closely, you must be doing a pretty spectacular job of controlling the variables, surface finish, in my mind, being one of the critical ones.

I just feel inferior 

JohnInCarolina

nolaegghead said:

Ozzie_Isaac said:

JohnInCarolina said:

kl8ton said:

JohnInCarolina said:

Plotting trajectories to strength surfaces, in principal stress space (projection onto sigma_3):



The green surface is our best guess of what the strength surface for this material could be.  The blue, red, and yellow lines correspond to an analysis of three different specimens of a notched Aluminum material.  The points where they end are where the specimens all failed.  The fact that they just touch the surface seems to indicate that failure is being governed by strength in this case, as opposed to energetics.   

What method is employed to cause failure?   Is this metal forming?  Metal cutting? Abrasive testing? Temperature testing?   Other?  I'm just curious as in my past, I did FEA on the feasibility of proposed tooling to produce automotive parts.  I'd evaluate. . . Er the computer would evaluate if a proposed forming process would result in product fracture or excessive thinning.  I enjoyed it.  

Here we are performing simple 3-point bend tests of beam-shaped specimens.  What we're doing is enhancing our understanding of crack nucleation vs propagation.  It turns out they seem to be governed by fairly different physics.  

We use FEA for the calculations, and compare results to experiments conducted at a lab in Tel Aviv.  I actually teach a couple of different graduate courses on linear and non-linear FEA here at Duke.  

Out of curiosity, how do you control the surface finish on your specimens?  You theoretical data matches the empirical data so closely, you must be doing a pretty spectacular job of controlling the variables, surface finish, in my mind, being one of the critical ones.

Are you suggesting microvoid coalescencence is purely a function of crystaline structure abnormalities in non-amorphic solids?

No, he’s asking why there doesn’t appear to be much of a stochastic element to the data, because with strength there typically is.

Foghorn

JohnInCarolina said:

nolaegghead said:

Ozzie_Isaac said:

JohnInCarolina said:

kl8ton said:

JohnInCarolina said:

Plotting trajectories to strength surfaces, in principal stress space (projection onto sigma_3):



The green surface is our best guess of what the strength surface for this material could be.  The blue, red, and yellow lines correspond to an analysis of three different specimens of a notched Aluminum material.  The points where they end are where the specimens all failed.  The fact that they just touch the surface seems to indicate that failure is being governed by strength in this case, as opposed to energetics.   

What method is employed to cause failure?   Is this metal forming?  Metal cutting? Abrasive testing? Temperature testing?   Other?  I'm just curious as in my past, I did FEA on the feasibility of proposed tooling to produce automotive parts.  I'd evaluate. . . Er the computer would evaluate if a proposed forming process would result in product fracture or excessive thinning.  I enjoyed it.  

Here we are performing simple 3-point bend tests of beam-shaped specimens.  What we're doing is enhancing our understanding of crack nucleation vs propagation.  It turns out they seem to be governed by fairly different physics.  

We use FEA for the calculations, and compare results to experiments conducted at a lab in Tel Aviv.  I actually teach a couple of different graduate courses on linear and non-linear FEA here at Duke.  

Out of curiosity, how do you control the surface finish on your specimens?  You theoretical data matches the empirical data so closely, you must be doing a pretty spectacular job of controlling the variables, surface finish, in my mind, being one of the critical ones.

Are you suggesting microvoid coalescencence is purely a function of crystaline structure abnormalities in non-amorphic solids?

No, he’s asking why there doesn’t appear to be much of a stochastic element to the data, because with strength there typically is.

Duh.

kl8ton

Our FEA was usually run with worst case scenario specs. Steel manufacturers had a range of what they could produce given a certain material callout. We ran stimulation at lowest grade.  

Forming thru a notch can prove problematic,  but keeping trim details with 3d shape on them sharp is very expensive.  

If we started having problems after hard tooling was made, we would send out the material for analysis to make sure it was what it was supposed to be.  

Foghorn

Sitting on an oceanfront balcony in St. Augustine Beach watching the waves, the pelicans, and tortoise copulation...

billt01

Foghorn said:

Sitting on an oceanfront balcony in St. Augustine Beach watching the waves, the pelicans, and tortoise copulation...

surface finish

Acn

Tapas from the place 2 doors down from our apartment.  Calamari, croquettes, gambas al ajillo, pinchos morunos, pan amb tomate, bread basket.  Not pictured is fried cuttlefish and plates of olives and fuet (thin sliced Catalan sausage).  

Grand total of our meal, including the bottle of wine on the table, and an orange fanta for SWMBO Jr?  €55 euro.  I could stay in Barcelona forever.

MediumRarely

Took a little walk this morning with my wife. A bit of wind, some rain, but 82F and a nice early morning jaunt.

TEXASBGE2018

Being driven nuts by a customer and thinking about whether I should look for a new job.

kl8ton

TEXASBGE2018 said:

Being driven nuts by a customer and thinking about whether I should look for a new job.

Every time I get a new job/career, the customers always find me!  Good luck with your decision.  

GrateEggspectations

nolaegghead

You: Excuse me, sir..?

Pianist, (slightly aghast): Can't you see I'm performing?

You: Would you happen to have some....Gray Poupon?

Ozzie_Isaac

GrateEggspectations said:

That looks beautiful, but a bit like a rough crowd.  Having to rope off the pianist and all.  That reminds me of the metal cages around bands in dive bars.

Ozzie_Isaac

JohnInCarolina said:

nolaegghead said:

Ozzie_Isaac said:

JohnInCarolina said:

kl8ton said:

JohnInCarolina said:

Plotting trajectories to strength surfaces, in principal stress space (projection onto sigma_3):



The green surface is our best guess of what the strength surface for this material could be.  The blue, red, and yellow lines correspond to an analysis of three different specimens of a notched Aluminum material.  The points where they end are where the specimens all failed.  The fact that they just touch the surface seems to indicate that failure is being governed by strength in this case, as opposed to energetics.   

What method is employed to cause failure?   Is this metal forming?  Metal cutting? Abrasive testing? Temperature testing?   Other?  I'm just curious as in my past, I did FEA on the feasibility of proposed tooling to produce automotive parts.  I'd evaluate. . . Er the computer would evaluate if a proposed forming process would result in product fracture or excessive thinning.  I enjoyed it.  

Here we are performing simple 3-point bend tests of beam-shaped specimens.  What we're doing is enhancing our understanding of crack nucleation vs propagation.  It turns out they seem to be governed by fairly different physics.  

We use FEA for the calculations, and compare results to experiments conducted at a lab in Tel Aviv.  I actually teach a couple of different graduate courses on linear and non-linear FEA here at Duke.  

Out of curiosity, how do you control the surface finish on your specimens?  You theoretical data matches the empirical data so closely, you must be doing a pretty spectacular job of controlling the variables, surface finish, in my mind, being one of the critical ones.

Are you suggesting microvoid coalescencence is purely a function of crystaline structure abnormalities in non-amorphic solids?

No, he’s asking why there doesn’t appear to be much of a stochastic element to the data, because with strength there typically is.

This exactly, the fact that the three data points shown land on the theoretical curve is extremely impressive.  From the material properties of the specimen to the quality of machining is impressive.  These data sets usually seem to come with all the caveats and explanations.  Even the best sets have a noticable distribution.

MediumRarely

Ozzie_Isaac said:

GrateEggspectations said:

That looks beautiful, but a bit like a rough crowd.  Having to rope off the pianist and all.  That reminds me of the metal cages around bands in dive bars.

Patrick Swayze, Road House - not.

Ozzie_Isaac

MediumRarely said:

Ozzie_Isaac said:

GrateEggspectations said:

That looks beautiful, but a bit like a rough crowd.  Having to rope off the pianist and all.  That reminds me of the metal cages around bands in dive bars.

Patrick Swayze, Road House - not.

Lol!!  That is exactly the movie I was envisioning.

HeavyG

Ozzie_Isaac said:

MediumRarely said:

Ozzie_Isaac said:

GrateEggspectations said:

That looks beautiful, but a bit like a rough crowd.  Having to rope off the pianist and all.  That reminds me of the metal cages around bands in dive bars.

Patrick Swayze, Road House - not.

Lol!!  That is exactly the movie I was envisioning.

Blues Brothers for me... "rawhide!".

Kayak

Ozzie_Isaac said:

MediumRarely said:

Ozzie_Isaac said:

GrateEggspectations said:

That looks beautiful, but a bit like a rough crowd.  Having to rope off the pianist and all.  That reminds me of the metal cages around bands in dive bars.

Patrick Swayze, Road House - not.

Lol!!  That is exactly the movie I was envisioning.

I was thinking of this:

https://youtu.be/QybXY1vWUxI

Ozzie_Isaac

Kayak said:

Ozzie_Isaac said:

MediumRarely said:

Ozzie_Isaac said:

GrateEggspectations said:

That looks beautiful, but a bit like a rough crowd.  Having to rope off the pianist and all.  That reminds me of the metal cages around bands in dive bars.

Patrick Swayze, Road House - not.

Lol!!  That is exactly the movie I was envisioning.

I was thinking of this:

https://youtu.be/QybXY1vWUxI

Haha!  Never seen Taxi, but looks like a good show.  Especially with Doc Brown in it.

Here is a Youtube chanel I very much enjoy:

https://youtu.be/ehQb3zQkUIc

GrateEggspectations

Ozzie_Isaac said:

GrateEggspectations said:

That looks beautiful, but a bit like a rough crowd.  Having to rope off the pianist and all.  That reminds me of the metal cages around bands in dive bars.

Only hit one dive bar.

SamIAm2

GrateEggspectations said:

You sir are living large and are truly blessed. What did the family think of the pianist?

Ozzie_Isaac

GrateEggspectations said:

Ozzie_Isaac said:

GrateEggspectations said:

That looks beautiful, but a bit like a rough crowd.  Having to rope off the pianist and all.  That reminds me of the metal cages around bands in dive bars.

Only hit one dive bar.

Wow!!  We have a different idea of dive bar!  That looks very nice.

Foghorn

Sunset and moon rise in St. Augustine.  We’re facing east but the sun hits the clouds and the sunsets are still great - especially when the moon plays along. 

FarmingPhD

Minor league hockey

Battleborn

FarmingPhD said:

Minor league hockey

We just built a new arena for our AHL team. They are supposed to open the building for hockey the first week of April. Pretty excited to go watch a game there. 

FarmingPhD

Battleborn said:

FarmingPhD said:

Minor league hockey

We just built a new arena for our AHL team. They are supposed to open the building for hockey the first week of April. Pretty excited to go watch a game there. 

Kids had a blast, forgot how much action there is in hockey which really keeps the kids attention. The company my wife’s sister and B-I-L work for owns the team and snagged free tickets. Staying at a hotel north of Naples, per @saluki2007 I’ve been paying attention to vehicles down here. They have not disappointed, BMW i8 roadster, Bentleys, corvettes are common, and stuff I don’t know what it is other than expensive.

Ozzie_Isaac

My form of meditation.