AN ANALYTICAL XRAY SERVICES LABORATORY
Feel free to call us: 940-784-3002

FCT 0027 Xray decal visual croppedWe’ve been working with XRD machines for about 40 years now and to be quite honest, very little has changed. Most of the really exciting advancements have been software based, but there have certainly been changes to the hardware as well. We’ve introduced a few ourselves such as the KSA-SDD-150 detector. Automatic anti-scatter and divergence slits, additional axes and degrees of control have all increase the versatility of these instruments and opened them up to more advanced and unique experiments, but nothing has had an effect matching the new crop of Position Sensitive Detector (PSD). These have been around for decades, but didn’t really become popular until the a solid state version was introduced. There are still some trade-offs as mentioned in our KSA-SDD-150 post, but when you need speed, a PSD is the way to go.

Until recently, the only option for clients looking for this kind of speed was either a new XRD or a refurbished Bruker D8 system with a LynxEye or Vantec-1. While the D8 is a great machine and the LynxEye is a world class detector, the cost is usually too much for academic or small labs to bear. This has all been changing recently with the introduction of a truly aftermarket detector system from FCT ACTech. No other company that we’re aware of has worked so hard to make their hardware as turnkey as possible so the user isn’t left holding a box of parts and an instruction manual.

We can now offer detector upgrades for D5000 Theta/Theta and D5000 T2T systems with kits soon to be available for D500 systems as well. Software integration with DiffracPlus (standard software for Bruker XRD systems) is seamless and full integration with MDI Datascan is very close to completion. The future is very bright for users of these XRD systems.

Contact us for more information on these detectors


NovaculitesiliconKey features:

  • Data collection at 30x the speed of a standard point detector.
  • Dramatic increase in throughput
  • Plug-and-play retrofit
  • Maintenance free (no gas charge required)
  • Stand-alone operation for custom experiments
  • Excellent angular resolution

 

Technical Specifications:

  • Maximum count rate: 500Kcps / pixcel, 50Mcps global
  • Maximum scanning speed: 120 deg/min
  • Angular resolution: 0.06 deg at 200mm radius
  • Strip pitch: 120um
  • Number of channels: 96
  • Angular span: 3.3 degrees
  • Energy resolution: <10%
  • Energy range: 4.5KeV to 17KeV, efficiency at 30KeV is 10%
  • Compatible with all common XRD tube anodes including Cr, Fe, Co, Cu, Mo and W.

XRD sample holders are easily the most common items we’re asked to machine. Sometimes it’s because they’re no longer available, but usually, it’s to accommodate some special application. Sometimes it’s as simple as making them from Aluminum to allow for cleaning with acetone or other harsh solvents. Other times it has more to do with the clients preferred style of loading or sample volume. The end result is that there’s very little consistency so our process needs to be as versatile as possible. This video highlights the most recent process. It’s hard to see exactly what’s going on through the coolant, but this is a test run of a program to cut special holders for 25mm filter membrane holders for respirable silica measurements (or anything else one might want to deposit onto a 25mm filter). It’s cutting the bottom of one holder and the top of another (each on its own side of the fixture).  A full load of these produces 6 complete holders for every run.

Siemens goniometers are about as sturdy as they come. Large diameter gears and bearings spread out forces across a wide area resulting in smooth and stable performance as well as very high load handling due to the added leverage of this arrangement. For this reason, they’ll run for many years even after the grease inside has become hard and contaminated with dust. Most users don’t even know their goniometer is getting stiff until we check it during a PM. Catching this before the goniometer starts to hang up saves thousands of dollars and weeks of down time. Our goniometer rebuild service involves complete disassembly of the goniometer down to individual ball bearings for a thorough cleaning. We’ve tried to duplicate this procedure on-site with very limited success as the large components are best cleaned in a full size solvent bath and it’s special brackets are required to avoid concentricity issues during reassembly. All the critical electronics are replaced during reassembly along with fresh lubrication. The best case scenario is that we catch issue far enough in advance to get a matching replacement goniometer rebuilt and shipped out. There are too many variants to keep rebuilt units in stock all the time. This way we only need to come to the site once to swap the goniometer and perform the necessary zero alignment. The old goniometer goes back in the same crate and we’re done in a day or two. Waiting till a hard failure of the goniometer means a trip out to identify the problem and disassemble the system. The goniometer is shipped in for a rebuild which can easily take a few days to complete before being shipped back along with a second on-site visit. I’d estimate the extra cost to be right around $6k plus the cost of shipping and two weeks of downtime. We certainly don’t mind going this route, but if it were my money, I’d rather spend it on a comprehensive check of the machine rather than emergency services.

These pictures are from one of our first full rebuilds. This instrument was installed in a D5000-MATIC instrument at a cement plant. I’ve never seen so much dust inside a goniometer. Another particularly rough one was from a horizontal goniometer on a single-crystal system at a university. The students had a terrible habit of breaking Si(100) wafers and dropping them onto the goniometer face. Those little shards made their way into the bearings resulting in a rather perilous rebuild with shards of Si throughout it.

Posted by: In: Uncategorized 12 May 2016 0 comments

IMG_20160428_120306

Everyone wants to see their instrumentation perform at its peak, but all too often, the instrumentation is not the weak link in an analytical strategy. We see this in WDXRF and XRD, but recently had the opportunity to work with a client on their OES sample prep. This large steel mill has been using an automated Herzog sanding machine for many years. I’ve seen it in action and it’s a truly impressive tool. The engineers at Herzog have decades of experience building automated prep solutions and definitely worked hard on the design. However, speed was the key factor when this method was developed. There are few ways to prep a metal coupon faster than running it against a sanding belt. The sanding method had the added benefit of an extremely hard cutting medium (usually Al2O3) which meant that a single preparation procedure could be used for all steel grades and even worked when careless workers chose to water quench hot samples rather than allowing them to temper a bit by cooling in air (making them extremely hard). The downside of this method comes down to surface quality. Sanding will always leave a rough surface with linear troughs/grooves which create a variable surface area as well as shadowing. These effects are detrimental to light element sensitivity and as tolerances are tightened, the lab supervisors were forced to look to other methods.

IMG_20160428_120412

 

We began talking about this project over a year ago when the WDXRF user mentioned the lower detection limits that were soon to be implemented. I’d had some experience with sample preparation by milling, but usually more exotic alloys. There are certainly more than a few options available for automated milling, but their high cost and space requirements put them out of the running for this situation. My recommendation was to purchase a lower level CNC milling machine and automate as much of the process as possible to simplify operation and limit opportunities for error. I’m happy to say that the first tests earlier this month were a great success. The coupons come out with a very smooth surface in about the same amount of time it took to run through the sanding machine before.

IMG_20160428_120323There are still some things that bear consideration with milled samples. Not the least of which is contamination from the cutter. This client is unlikely to be bothered by Al2O3 from their sanding media, but small amounts of Tungsten Carbide steel (WC) rubbing into the surface could present an issue as cutters wear out. Luckily, the tools we’re using are indexable and not too expensive which allows users to change cutters frequently. It’s important to maintain a sharp edge and correct settings for this type of work in order to avoid “rubbing” through the material. This occurs when the tools is rotated too fast or fed too slowly. Material is pushed out of place rather than being cut. This causes contamination, premature tool wear and smearing of the surface. All of which have a detrimental effect on the analysis. I spent a solid day working out the initial conditions and there will still likely be many adjustments and changes before this becomes the primary production method.

 

All in all, this was a great project to work on. The improved detection limits will dramatically improve their analysis of light elements, the automated vise and mill will make it even easier and faster to prep material than before and we’ve done it all at a fraction of the cost expected. One thing I should note here is that this particular milling machine was chosen due to its exceptionally small size and low cost which were key requirements of this job. Given a less restrictive environment, I would have recommended a much different solution.

Posted by: In: Uncategorized 12 May 2016 0 comments

The last post in this series showed what can happen to the optics path of an XRD system in the wrong environment after several years of neglect. The end result of this kind of build-up is attenuation of the beam. The user will see this as a loss of intensity, but little else. In the XRF world, things are a little different because everything in the beam path can be expected to fluoresce as well as attenuate the beam. Depending upon the position and type of material, this can cause a range of interesting effects.

In the most basic case, the beam is simply attenuated as it would be in the XRD causing a loss of intensity. This would be the case with certain types of blockages in the incident beam. Several years ago I got a call from a senior tech at Bruker who was trying to help a client remotely. They’d been running fine until their intensities abruptly dropped nearly in half across the board. Checking the electronics and searching for evidence of a broken sample yielded no answers. Running previously analyzed samples proved that this was definitely not sample related. Owing to the urgency of their situation, I flew out right away with a solid kit of spare parts only to find a Post-It note sitting right on the port of the tube. Just in case there was any doubt, it had the identifier of the first sample which exhibited the symptoms written on it. It must have gotten stuck to the bottom of the cup before being loaded into the autosampler and carried all the way into the measurement position. We had a good laugh (and still do).

20131126_123820

 

Other attenuation issues aren’t so obvious. A client running heavy greases in a He environment saw a 90% drop in light element intensity while heavy elements performed fine. After some remote trouble-shooting we were able to eliminate several possibilities, but fell short of a real solution. As it turns out, the issue was caused by a crack in one of the He flush lines. These instruments don’t simply flood the chamber with He during this cycle. Rather, they start by opening two He valves (one high flow and one low flow) while turning on the vacuum pumps. Once the lines are purged, the valves close and a vacuum is pulled on the chamber. At this point, the pumps shut off and the chamber is vented to He. The split hose was leaking a very small quantity of air into the chamber at the same time it was venting to He. Even this very small amount of air was enough to devastate light element intensities.

20150107_153115-LowThe pictured issue is another very common problem. Dust from powdered samples or worse, spills or drips from liquid samples can build up on the port of the tube. The result of contamination like this is usually minimal attenuation, but it can result in a very noticeable change in the reported intensities for a given element. Most users would catch this when running a monitor standard and many would simply run a drift correction to compensate, but the best course of action is to get your service provider involved right away. They’ll be able to assess the situation quickly and might offer a better solution than simply patching the issue with a data massaging correction. At least they’ll be in the loop if the symptoms become more serious.

There are some options for keeping your port safe from this kind of contamination. We like superfluous films which keep bits of material from falling onto the tube. Mylar, Kapton (Polyimide) and Prolene (Polyprolylene) are popular choices depending upon your application. Bruker systems starting with the S4 offer a filter position with a Be shield which protects the tube window itself and works well. More exotic options (inverted optics) promise to eliminate this problem, but this offers its own challenges. For instance, the users most concerned about this kind of contamination are running liquids. Pulling a vacuum on a liquid cup makes a mess no matter where your optics are and running a liquid in an inverted cup is an added complication and opportunity for error that we’d prefer to avoid.

Posted by: In: Uncategorized 26 Apr 2016 0 comments

Most of you already know that CNC machining has been a hobby of mine for several years now. Few things are more mesmerizing to me than watching shards of metal fly off a block until the part I designed emerges at the end. I got a new project last week that I thought would be fun to share and in case you’re curious, I actually run the mill in my home garage so I can work into the evening without sacrificing too much time with my wife and kids.

DSC_4996-Low

The first and second generation D8 XRD systems came with a very large octagonal housing. These are very useful when you need lots of space for extended optics, accessories or anything else you might need to store. They are particularly hard to ship though. The factory method calls for lots of bracing and crating to keep the large glass panels safe, but when one of these is shipped to us, it rarely gets this treatment. As long as the handlers are careful, this isn’t a problem, but we’ve still seen many of them with the handles broken off the bottom of the doors. Replacements are available directly from Bruker, but I’m not one to pass up a chance to run the milling machine and 3D printer.

These new Al handles are beautiful and were a great project for me to get familiar with the new mill. I’ve made several extra sets just in case the need arises in the future too.

Posted by: In: Uncategorized 30 Mar 2016 0 comments

I’m continually amazed at just how many XRD users we encounter who are only vaguely aware of what their machines can do. These instruments are relatively simple in mechanical terms, but the data they generate can unlock an amazing array of information about the sample. We’ve traveled all over the country over the last 40 years and spoken with countless XRD and XRF users. Many of these are novice users who understand the basics of their application, but little more. Some were relying on courses they’d taken in college many years before. Many had attended one class or another, but rarely felt they came away prepared for the work they’d be doing. I’ve heard so many people describe the information going “straight over my head” that I’m convinced there’s a better way to train users on the broad scope of analyses their diffractometer can perform.

We began offering training classes as soon as we started Texray hoping to fill the gap between tedious trial-and-error and, for some, ineffective large format courses. Along the way we’ve expanded our class offerings to include everything from basic theory (even general chemistry) to advanced analytical techniques such as Rietveld refinement among others. Texray is also certified by MDI to offer field training classes on all their analytical software. This allows us to arrange for demo licenses of some very powerful software for all attendees for the duration of the class.

Flexible:

Many of the clients we’ve worked with have small gaps in their knowledge which leaves them lost on the first day of a large format class. In our small groups, the curriculum is determined by the current knowledge level of the attendees and their own goals. No time needs to be spent on applications which they’ll never use and no one gets “left in the dust” on day one. Multi-stage classes begin with basic theory and progress to advanced techniques to allow for new users to get their feet wet and experienced users to broaden their skills all in a single session. Attendees may jump in and out according to their skill level.

Economical:

When a company is asked to send an employee for outside training, it usually requires a full week of their time during which they’re not covering their usual responsibilities. Travel costs and down time usually mean that a given lab will only send one or two primary users to the training class. With an on-site course from Texray, attendance is unlimited. Training two or more users represents a huge cost savings. There’s no faster or more economical way to bring your whole team up to speed.

Effective:

A highly skilled instructor comes to your site. You’ll work with your own hardware and software to eliminate the learning curve which can become an significant obstacle after large group courses. You’ll receive training targeted specifically to your applications and at a pace dictated by the attendees, not a fixed curriculum. All attendees will be provided with temporary licenses for Jade 2010 software for hands-on work throughout the class.

Posted by: In: Uncategorized 24 Mar 2016 0 comments

I’ve been wanting to write this post for a long time. I think about it every time we get a call or email from someone who wants to talk about an application that’s a little “outside the box” or just making contact to learn more about what we do. The conversation always follows a similar pattern through which they explain what’s needed and I get to offer advice based on my experience, or lack there of, with that type of work. Every time I think I’ve heard it all, I’ll get a call for something completely new. It’s a fascinating world we live in and a great time to be a scientist. That brings me to my point, these callers always seem surprised that when they call, the phone is answered by someone who is technically knowledgeable, at least familiar with the science and quite happy to talk at length about their needs. I tell them all the same thing, “This isn’t just a job, we live for this stuff.”

image1001

CNC machining is a relatively small part of what we do at KSA and Texray, but it’s a personal hobby I enjoy quite a bit. I’ve cut many of these SS branding iron heads friends and charity auctions. They’re fun, not too complicated and really cool.

image003

Posted by: In: Uncategorized 24 Mar 2016 0 comments

Preventative maintenance has always been a difficult subject for me. The manufacturers all recommend an annual visit to go over their instruments in the hopes that small issues would be dealt with before they became large issues, but it’s never easy to tell a client that their perfectly functional system requires thousands of dollars in maintenance. That being said, over the last 40 years, we’ve performed countless PM routines all over the world on at least 13 different models of XRD and XRF instrumentation and almost every one of those visits has turned up at least one issue which needed attention for one reason or another. This will be the first of several posts detailing various problems we’ve encountered during these visits.

A long time client at one of our most prestigious national laboratories had gone several years without any maintenance being performed on their Siemens D500. Over that time, corrosion built up in this small receiving area before the incident beam optics. I should be very clear that this has no effect on the shutter assembly, fail-safe features or safety in general. However, if left unchecked, flakes will eventually fall into the beam path. The symptom is simply that intensities are lower. This is not the first time we’ve been called out to replace a tube only to find that the low intensities were due to attenuation. Running through a basic PM before installing the new tube saved $6000 of your tax dollars.

image011

Posted by: In: Uncategorized 07 Sep 2015 0 comments Tags: , , , ,

Every once in a while we get a call for components destined for custom equipment. NIST has built some extremely precise XRD instrumentation from various base components. These are operated in highly controlled environments to qualify certified reference materials (CRM). Some of our other clients have built much more proprietary, but no less impressive systems which I’d love to show in detail if the designs weren’t closely guarded intellectual property.

One of the most interesting and exciting projects we’ve seen recently is the hard-xray monochromator system developed by Dr. Gerald Seidler of University of Washington and his colleagues. The instrument itself has myriad applications, but the general idea is that many experiments which currently require synchrotron time can be performed in a laboratory setting. We’ve worked on other projects like this which were meant more qualification systems to avoid wasting synchrotron time if the experiment didn’t actually require it, but Dr. Seidlers instrument is geared toward bringing XAFS, XES and XANES right into the lab setting.  Read the full paper here.Capture