Recent content by engineer23

Heat transfer -- aeroheating and material thickness I'm trying to size the thickness of a shroud to encapsulate a payload on a small rocket. We're using carbon fiber pre-preg (k=6.83 W/m-K) and (per the aeroheating analysis based on the trajectory) the max heat rate is 908 kW/m^2. The...

We are looking at designing a 10" diameter, 48" long payload shroud (Ogive nose cone) for a large hobby rocket. We have done an aeroheating analysis based on the trajectory, so we have the max temp. experienced during ascent at several body points. We want to make the shroud out of composites...

Hi all! This forum has been very helpful to me in the past, so I thought I would post this question here. I have what are basically machine tools that I am trying to examine in the SEM (I also use profilometry to gauge surface roughness). After use, the tools have residual Aluminum on...

Dried Superglue -- flammable? Is dried superglue flammable? I am using superglue to deposit abrasive particles in a groove which runs the length of an aluminum joint. The joint is welded using a solid-state process (no melting). Should I be concerned about flammability? I have used wood...

I am looking for an introductory book on sensing using acoustic emissions. Specifically, I am hoping to use acoustic emissions signals to detect tool wear (and classify the wear as mild, severe, etc.). Does anyone have a recommendation? Something with examples using LabView and/or MATLAB...

^Thank you. That paper is very helpful. I ordered some WC tools to be coated with diamond (in search of the ever-elusive wear resistant tooling). I'm guessing now that these are in fact WC-Co tools? That would explain the difficulty that the diamond lab has encountered in attempting to coat...

Most papers I have found focus on coating a base material of WC-Co. Is WC always alloyed with Cobalt? It is possible to have a tool that is WC alone? It seems that the alloying is done to make the material less brittle (and thus avoid fracture of tools in machining applications). I also...

Does anyone have any expertise in the coating of WC tools? Are these tools coated by a deposition process (ex. CVD)?

Does anyone know or know where I could find the average mass of a single lymphocyte? Specifically, a T-cell?

Homework Statement The problem is to design a cantilever beam with a certain resonant frequency. Homework Equations w = sqrt (k/m) The Attempt at a Solution I know k for a beam and m can be written as density * volume. My question deals with the w. If I am given a...

Does anyone know where I could find the masks and steps that are used to manufacture a microwheel/gear?

I think you may be right. The diagram definitely indicates deflection is downard, so I think the values they report are deflection from initial position (absolute). The only other thing that bothers me is that deflection appears to decrease with increasing hydrogen concentration. This...

Microcantilever---direction of deflection I was reading a paper on a microcantilever-based hydrogen sensor. Here's how the sensor works (as I understand it): The cantilever is coated with Palladium film. In the presence of Palladium, diatomic hydrogen splits into H atoms, which are absorbed...

Is there a website or book that lists hardness values for the following: Polycrystalline Boron Nitride Molybdenum Tungsten Carbide Diamond h13 B4C SiC Al2O3 I've tried www.matweb.com, but they only have hardness values for some of these materials. I can't locate PCBN in their...

I am looking at the derivation for an expression that relates the concentration of an oxide to time. It appears that to do this, the author takes the limit of sqrt(A+Bt), where A and B are constants as t approaches zero and infinity. Is there an easy way to do this without making assumptions...