New HEN Cup: Continued by David Sparkman, MeltLab Systems

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1 Last month we mentioned the new Heraeus ElectroNite (HEN) cups (that are now available from some distributors) and the possible issue that the liquidus arrest might be affected by the faster cooling rate. This report details some additional areas we are looking into: But first, their claims on the new cup: 1. Accuracy of silicon and carbon prediction improves 10% 2. 20% faster measurements 3. Enhanced welding method improves thermocouple strength 30% 4. Cement mixture improves shelf life from 1 year to 3 years 5. Stronger core sand improves cup engagement on the stand 6. 15% reduction in fume generation when iron is poured 7. More obvious plug-in orientation identification 8. Packaging remains the same 100/box and 3,000/pallet (Source: Heraeus Electro-Nite Foundry Market Product Catalog) For starters, who knew that they had all these issues? Some of them we have been pointing out for years. Did they finally listen? - Maybe. Did they consult with us on anything? Nope. There is still more testing to be done but here is our first in depth look into these claims and what they can still do to improve their product: 1. Accuracy of silicon and carbon prediction improves 10% Maybe we have not seen the liquidus recalesence that plagued the previous design as well as the boiling effect of the older style tellurium blob which tended to burn away both carbon and silicon as we have documented in the past.

2 2. 20% faster measurements? This appears accurate. We took 21 samples with the following distribution: Time to Eut # Occurrences a. 140 sec 1 b. 145 sec 3 c. 150 sec 1 d. 155 sec 5 e. 160 sec 3 f. 165 sec 3 g. 170 sec 1 h. 175 sec 1 Standard cups seem to be taking seconds, so this assertion seems to be true and even a little understated. (Note that the time is based on the start of thermal analysis to the Eutectic point when most instruments will calculate Carbon and Silicon.) The maximum temperature of the sample and the amount of iron actually in the cup will influence the time the sample takes to cool to this point. All these samples were taken by normal trained foundry personnel charged with this duty. 3. Enhanced welding method improves thermocouple strength 30% Well, it is about time ElectroNite moved away from flame welding. MINCO, Reliacheck, Matrix, Ecil and others did this long ago. HEN s claim to be using lasers is interesting. In the past, a 2% failure rate on cups was considered normal 2 bad cups per box. These failures were caused by a variety of reasons, and included operator errors as well. However, from what we have seen with the cups, the failures are more likely to be from one s testing equipment not being adapted to these faster cups. The good news is your MeltLab can be quickly adapted to correct these issues by one small change, and can therefore work with everyone s cups. 4. Cement mixture improves shelf life from 1 year to 3 years. Probably true as far as the 3 year part. The boiling issue: the problem with the Sodium Silicate/Bentonite/Tellurium mixture of HEN s previous design is that it retained and absorbed moisture causing excessive boiling. We have affirmed for a long time that boiling is not necessary. As far as the new cement mixture it may indeed be producing less boiling and allowing for a fuller sample good news for accuracy and consistency of results when using your MeltLab. However, one beneficial side effect of the excessive boiling was that it did reduce the maximum temperature notably, so if you are sampling very hot iron (2800F), you may run the risk of melting thermal couples with the new (lower boiling) design.

3 One other item regarding the Tellurium blob: we have seen instances where the blob dislodges from the cup presumably from a combination of the shipping and not enough adherence to the bottom of the cup. (A cup without its Te is useless for chemistry, but if you are using your MeltLab for microstructure, then it can be used for that) 5. Stronger core sand improves cup engagement on the stand. A good idea indeed but what they don t mention is that they have adopted one of our MeltLab tricks and now have a space or gap of about 5 millimeters between their cup and stand to keep heat farther away from the stand connector thus preserving it s structural and insulating integrity. The MeltLab cup connector has had this for years. I guess imitation is to be considered a form of flattery % reduction in fume generation when iron is poured. OK, but where does the fuming come from? Is it from the sodium silicate, or from the tellurium? Have they reduced the tellurium now? We have hearsay evidence from a former Electro-Nite employee that the reason for this smaller cup is to reduce the amount of tellurium being used because of its increasing expense. 7. More obvious plug-in orientation identification not a bad idea. Now how about the things they didn t mention? 1. Wire certification? still missing. Special Limits wire, which all cup manufacture s use, is +/- 2 degrees F. Every spool of wire received by the manufacturer comes with a certification to prove it is within this limit. ElectroNite has steadfastly refused to furnish this information except to special customers. Not having this calibration information available necessitates the more quality oriented foundries to recalibrate their carbon and silicon for each different shipment of cups. MeltLab has a wire bias variable that, if entered, will rebalance the equations for carbon and silicon for each shipment. Incidentally, L&N, Matrix, and MINCO did report this value from the wire certs. HEN stubbornly refuses this saying they only use the best wire. We have seen with the introduction of this new cup that despite this claim, changes and calibration were needed.

4 2. Sample weight to calculate cup fullness If you calculate the volume of the cup and compare it with the average weight of the cooled iron slug you can see how easy it is to fill the cup. The old cup routinely produced weights that were only 65-80% full due to the spitting of iron from the cup. New HEN Cup and cup fullness: We asked one foundry to provide us with some weights (using the new HEN cup) and got the following: I have collected 11 samples and got total weight grams and average weight makes gr for 11 samples. Here is what we got from sampling cups one by one as weight of iron slugs: 1) grams 74% full 2) grams 70% full 3) grams - 84% full 4) grams - 87% full 5) grams 82% full 6) grams 92% full 7) grams 80% full 8) grams - 92% full 9) grams - 83% full 10) grams - 90% full 11) grams - 75% full Assuming a density of 7.87 grams per cc of Iron, with the new cup we calculate a volume based weight (at 100% full) of 263 grams. So, we are filling on average 82.6% of the volume of the cup in the sample. This suggests there may still be some difficultly filling the cup all the way. Older HEN Cup: QK200 A second foundry provided us with weights using the older style QK200 HEN Cup. In 10 samples the average weight was 295 grams. Now the QK200 has a significantly larger volume and hence a proportionately larger theoretical max weight of 407 grams, therefore the average cup fullness using the older HEN cup was 72.4% or about 10% less fullness than the new HEN cup. At a third foundry, the average fullness of the old cup was even worse over a 10 cup average measuring about 64% or almost 20% less than the new cup. This suggests that the new Ceramic/Tellurium cement mixture may indeed be producing less boiling and allowing for a fuller sample better news for accuracy and consistency of results when using your MeltLab but still not very good.

5 Non-Te or Plain As-Cast Cup We poured and weighed one sample (from a cup that had lost its Te blob mentioned above) and therefore solidified as an as cast sample. We expected to see a higher cup fullness without the boiling from cement mixture and in fact we did the sample weighed in at 386 grams and that converted to a cup fullness of 95%. This agrees with what we have seen in other companies non-te cups as well and again illustrates that while HEN s new cup is improving in producing a lower-boiling cup, there is still progress to me made. Side Note: to get the best analysis, the thermal couple needs to be in the center of the thermal mass of the cup. If the cup is inconsistently filled, either due to operator or cup design, then the repeatability suffers. While HEN has made improvements in cup fullness/lower boiling in the new HEN, we have still seen better results. 3. Pricing secret as usual. Pricing includes three components: ElectroNite selling price, volume discounts, possible distributor markup, and of course shipping/handling. We have reports of prices as high as 1.80 per cup (not including S/H). We would like to encourage foundries to share their pricing with us. Are you getting a good price or has ElectroNite found a new way to generate revenue? Knowledge of market prices will help foundries get the best deals so let us know what you are paying and we will share keeping our sources private of course. 4. Three recommendations in using the new HEN cups since these cups cool faster, yet don t boil as much and may have less tellurium we suggest a few simple things to do when using these cups: a. Keep the cup full. The arrests are weaker and you need that extra iron. b. Keep the cup up to temperature (but not overly hot) by putting extra iron in the spoon to maintain heat. But if you have a problem of melting the thermocouple because you have very hot iron, disregard this advice. c. Adjust your Liquidus Detection from 1.0 to 2.0 if you have a MeltLab. (See our May Newsletter for instructions on doing this) If you don t, and keep missing liquidus, buy a MeltLab we can work with all kinds of cups.

6 Conclusion We are glad to see ElectroNite finally address some of the issues with their cups. These solutions may cause some problems with their older TA equipment, but we assume they have fixed their newer equipment to work with their new cups. It is not clear that all the issues have been resolved, but overall, we believe it is a move in the right direction. So the next time HEN recommends that you buy a new ElectroNite instrument (to better utilize their new cups difficulties in reading the arrests) why not consider a MeltLab instead? Our system in addition to providing Microstructural analysis and superior Chemistry accuracy can be configured to succeed with any new cup design and has been doing so for the past 25 years!