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3.7 Accessing MSC.Mvision Data
3.7.1 In-House Data Access
MSC.Mvision is a materials data management system marketed by MSC.Software Corporation.
This family of products includes both stand-alone (MSC.Mvision Builder and Evaluator) and enterprise (MSC.Enterprise Mvision) systems, in addition to off-the-shelf materials property databases, that assist the designer or engineer in evaluating and selecting the best material for his or her current application. Many companies use MSC.Mvision to manage it's internal materials knowledgebase, automating the flow of materials property information from test data, through reduction, compilation, modeling, and then directly to the engineer's design, analysis, and manufacturing codes. As such, MSC.Mvision provides an electronically accessible, consistent, and auditable archive of a company's materials experience. With access to comprehensive materials data, manufacturers can exploit materials as a design variable.
There are now over 40 commercial materials publications formatted for use by MSC.Mvision software. Categorized by type, they include Standards data, Reference data, Producers data, and Test data. The Standards databanks are of particular interest to the user of MSC.Fatigue, as they include stress-life curves for a variety of materials. The current selection of Standards Databanks includes:
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Mil-HDBK 5 of Aerospace Metallic Materials•
Mil-HDBK 17 (2F, 4F, and 5F) - Polymer, Metal, and Ceramic Matrix Composites•
ESDU Metallic Materials Handbook•
UDRI PMC-90 (Polymer Matrix Composites)The MSC.Fatigue Databank provides a compilation of fatigue test data for over 200 metals that is available free of charge to all MSC.Mvision users.
The following sections describe one technique for extracting materials information stored in MSC.Mvision Builder or MSC.Mvision Evaluator for import to PFMAT, MSC.Fatigue's Materials Database Manager. This procedure accesses MSC.Mvision's spreadsheet capability and an external function delivered with MSC.Fatigue to access S-N curves from Mil-HDBK 5 Databank. It is assumed that the user is familiar with MSC.Mvision Builder or MSC.Mvision Evaluator and it's spreadsheet capability. If this is not the case, please refer to the MSC.Mvision Builder and Evaluator User Guide.
There are basically five steps in which must be followed to extract a S-N curve from MIL-HDBK-5F and convert them into a form that MSC.Fatigue will accept in its materials database. The steps below assume you are on a UNIX system.
STEP 1: Create the functions that will be necessary to extract the data from MSC.Mvision. This is done with MSC.Mvision’smake_mvfuncutility. There are two FORTRAN source files that need to be compiled that are found in thematsdirectory of the MSC.Fatigue delivery and are calledmil5fat.fandoption .f. Place these in a work directory and invokemake_mvfunc. (Typically this utility is found in/mvision/bin/make_mvfunc.) It will find all.ffiles and compile them. The executable name will bemvfuncwhich you should renamed tomil5fat.
Note: This access to MILHDBK-5F databank is meant to be an example only.
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STEP 2: Create a local materials database. This can be done by running MSC.Fatigue’s Materials Database Manager, PFMAT. Loading any material into dataset one and edit it (use the
<RETURN> key when asked for a password). Back out of the edit and exit PFMAT. A copy of the central database will exist in the local directory. Another way is to use the PFMAT create option and initialize a new, empty database. Give the database any name. A file calleddatabase.mdbwill be created in the local directory, wheredatabase is the name it was given. A copy of the central database will be callednmats.mdb. The database MUST must be located in the local, working directory.
STEP 3: Bring up the MSC.Mvision Materials System Builder which is done generally by typing the symbol mvision at the system prompt and then supplying a device driver
definition.
STEP 4: Open MIL-HDBK-5F databank by clicking on DESIGN at the bottom of the screen, FILE at the top of the screen, OPEN_DATABASE underneath FILE, and then double click with the mouse on /mvision/db/mil5f.des(R0).
STEP 5: Open the spreadsheet that is delivered with the MSC.Fatigue system. It is advisable to make a copy of this spreadsheet in the working directory. The name of the spreadsheet is called mil5fat.spd and can be found in the MSC.Fatigue delivery directory structure in the mats directory. Opening the spreadsheet is accomplished once the databank is opened by picking RUN at the top of the screen and SPREADSHEET in the bar under RUN. A spreadsheet appears. Chose Open under the File menu. A form asking the identify of a spreadsheet file appears. (Cells P10 and AE4 may have to be edited to include the full pathname of the function calls.)
STEP 6: Fill out the spreadsheet according to its instructions. These are explained below. The spreadsheet is not protected (there are no locked cells) and is therefore subject to anything the user may advertently or inadvertently do. For this reason it is advised to use a local copy. Of course the spreadsheet must be saved to permanently change anything.
The first screen shown on the spreadsheet looks as follows:
A B C D E F
1 S-N Curves from MIL-HDBK-5 for MSC.Fatigue 2
3
4 1. Enter the search criteria:
5 UNS= *4131* Minimum Maximum
6 Common
Name=
* Mean Stress 50 10000
7 Heat Treatment=
* Stress Ratio -10 10
8 From = * Kt 0 10
9
10 2. Check the material selected. If this is not the correct material,
The first step that is asked for is the search criteria. In cells B5:B8, enter the UNS number, the Common Name, the Heat Treatment, and the From, respectively. In our example, we are using wild cards (*) to indicate that we wish to retrieve everything. For the UNS number, we wish to retrieve everything with the sequence 4130 in it.
In cells D6:E8, enter the Mean Stress, Stress Ratio, and Kt ranges of interest. A minimum and a maximum value for each must be supplied. Changes to any one of these items is effectuated by placing the cursor in one of the cells. The top formula bar will become active in which any changes may be entered. As soon as the RETURN key is pressed, the search will begin and the spreadsheet will update with the newly found materials.
A list of materials found is given beginning at row 19 and continues for as many materials as were found. The material that will be processed; however, is the very first one, which is also reported in row 15. The second step is to continue refining the search criteria until the exact material desired shows on line 15.
11 alter the criteria in Step #1:
12
13 Material to be sent to MSC.Fatigue
14 UNS CNAME TREAT FORM MSTRESS SIG_RATIO
15 G41300 Low-Alloy
Steel
Ftu = 180 ksi Sheet 50
16
17 Other materials which satisfied the search criteria
-18 UNS CNAME TREAT FORM MSTRESS SIG_RATIO
19 G41300 Low-Alloy
Steel
Ftu = 180 ksi Sheet 50
20 G41300 Low-Alloy
Steel
Ftu = 180 ksi Sheet 50
A B C D E F
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For the next step, scroll the spreadsheet horizontally until columns I through N show:
Look at the S-N curve graphically and determine where to place the endurance limit. The S-N curve should automatically be replotted showing the placement of the endurance limit when cell J5 is modified. Resize the windows or pop one in front of the other to see the curve if necessary.
A rule of thumb is to place the endurance limit at the stress level where the first data points being to run out to infinite life.
Now scroll the spreadsheet horizontally again until columns O through T are visible.
I J K L M N
1 2 3
4 3. Use the plotting window to adjust the endurance limit:
5 Endurance Limit=
1.5 ksi
6 7 8
O P Q R S T
1 2 3
4 4. Give the material a MSC.Fatigue name and comment:
5 MSC.Fatigue Name (32 char.
max.) =
steel1
6 MSC.Fatigue Comnt (64 char.max.)=
project 55B
7 8
In cell Q5, put the name of the material by which it will be known in the MSC.Fatigue materials database (a maximum of 32 characters). In cell Q6, put a comment (a maximum of 64 characters).
Notice that in cells P13:P20 are the parameters calculated from the S-N curve data that are necessary to be downloaded into the MSC.Fatigue material database. The database name is callednmats.mdb. When satisfied that the correct material and data have filled in all the appropriate cells correctly, place the cursor in cell P10 where the external function MIL5FAT resides and hit the RETURN key. (Note the path of the mil5fat function, cell P10. It may have to be edited depending on the location of the MSC.Fatigue executables. Cell AE4 also uses an external function call which will need the same path. Save the spreadsheet with the correct path.) This will initiate translation and will place the material in the database. These steps must be repeated for as many materials as are desired to bring into a MSC.Fatigue materials database.
Pitfalls to Avoid:
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Before attempting this make sure there is a local MSC.Fatigue materials databasenmats.mdbfile (or a user defineddatabase.mdbfile).
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Make sure there is no material of the same name as the one being loaded. Check thebatlog.lstfile produced by PFMAT when run in batch mode to see if the material was properly loaded.
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If the data did not load at all, check to see if the filemil5fat.matwas created which contains the PFMAT batch load commands. If it does exist, try using the command pfmat @mil5fat.matto load the data manually, outside of the MSC.Mvisionspreadsheet. SeePFMAT in BATCH Mode(p. 125) for an explanation of this operation.
9 5. Write the following material to the MSC.Fatigue database:
10 <return>
here->
steel1 S-N curve loaded OK
11 to add to MSC.Fatigue 12
13 Name = steel1
14 Comment = project 55B 15 Reference =
MIL-HDBK-5F
16 E1 = 199948 MPa
17 UTS = 620.5281 MPa
18 SRI1 = 4310.729 MPa
19 B1 = -0.1326177
20 SFL = 206.8427 MPa
O P Q R S T
Main Index
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Make sure that the external function in the MSC.Mvision spreadsheet (cell P10) can be found. When the cursor is placed in cell P10 note the name of the external function in the formula bar. If the installation of MSC.Fatigue has been followed properly, there should be no problems (except for editing the path in cells P10 and AE4). Make sure that the proper link to MIL5FAT has been created. MIL5FAT calls PFMAT, which must be in the users path or properly aliased or linked.•
Check to see that the Young’s Modulus (E1) and Ultimate Tensile Strength (UTS) are what is expected. Due to a MIL-HDBK-5 limitation not all datasets have an E and UTS associated with them. When this is the case, the spreadsheet extracts the E and UTS of the first material encountered with a UNS and CNAME of the type selected. If the E and/or UTS is not what is expected or wanted, edit these values in PFMAT.Other used areas on the spreadsheet are for work space.
This spreadsheet can be customized by the user if it does not perform the needed functions or it is desired to customize it for another databank. Two external FORTRAN functions are called during the execution of this spreadsheet, the source of which is delivered with the MSC.Fatigue system and can be found in thematsdirectory. These two function calls are used in cells P10 and AE4. The source files are calledmil5fat.fandoption.f.
To compile these functions after editing the source code: