Most Common issues in Stainless Steel Lost Wax Casting

In the moulage à la cire perdue en acier inoxydable process, two molds are used. The first is made of a metal. It can be easily worked in the inverted shape of the piece. This comes in two halves usually.  Then, this mold is filled with wax to form the models. Hence, it is its final shape.

How stainless steel does lost wax casting model work?

These models are placed in a box. Moreover, these are filled with foundry sand. Later, an operator gives it heat until the wax melts. Similarly, he drips and another mold with the inverted shape of the piece.

This yes is filled with the molten metal. In addition, it gives rise to the piece. The advantages of this process are that several parts can be produced. Similarly, all parts come in a series with a high degree of detail and practically finished. Subsequently, the disadvantage is that the size of the pieces is limited.

What is casting?

The casting is the process where we mold different objects for multi purposes. In simple words, a metal comes in liquid state first. Later, it goes into a mold. Later, we can develop different shapes via moulage à la cire perdue en acier inoxydable. So, we can use these molds for various industries.

In many cases, casting is the simplest and most economical process of producing a part.

The foundry can give rise to finished parts, already in their final shape, or not. In this case, they can undergo mechanical forming processes:

• dimensional adjustments
• welding or machining

But, in general, castings go through finishing processes such as:

• Grooving
• Machining
• and deburring

When necessary, the parts can also undergo heat treatment. It is to provide greater resistance since the moulage à la cire perdue en acier inoxydable have less mechanical resistance.

How to transform the wax model into metal through lost wax casting?

Wax modeling is a jewelry technique to create shapes by sculpting the material. The result is a piece of wax. Moreover, it must be turned into metal by casting with lost wax.

Do we know this process?

The first step is the handmade production of the model in silver or wax. Therefore, we have two different starting points. It depends on the material in which the prototype was made.

To transform the wax piece into metal, the model is attached to a rod, also made of wax. It forms a “tree “also. As the process takes time and energy, usually the moulage à la cire perdue en acier inoxydable completes with several parts in the same structure.

Moreover, these models can be different too. The final formation of the structure resembles a tree. This “tree” is placed inside a metal cylinder. And the calcium sulfate coating is poured into it.

Wax trees for the stainless steel lost wax casting process

After the coating hardens the cylinder gets heat to remove the wax. This expels, leaving empty spaces with the negative forms of future pieces.

The metal is injected by centripetal force via moulage à la cire perdue en acier inoxydable. It occupies the empty space left by the wax. After the metal has hardened, the coating is removed with cold water jets. The metal parts are removed from the “tree” with special pliers and go for assembly and finishing.

Serial reproduction

It is necessary to make copies of this piece or if the model is made of metal. The process begins by removing a rubber mold. This special rubber covers the pilot piece and is vulcanized. After heating, the rubber acquires a firm consistency.

Then, the rubber is opened, the pilot piece is removed. And, as a result, we have the negative shape of the pilot piece inside the rubber.

Models and rubber

By pressure, melted wax is injected into the mold. When the wax cools, we have a copy of the metal piece, only in wax. The wax piece is removed from the rubber mold. And it is ready to be used again. We can make as many wax copies as necessary.

The wax pieces are fixed on rods by stainless steel casting. It is also made of wax, forming a “tree”. And it follows the same process described above.

Stainless steel lost wax casting Problems

Some problems can occur during lost wax casting. The reasons for these defects to occur are diverse. Some of these causes are:

1. When a hole occurs: poor quality wax or coating, overheated metal
2. External balls occur: weak vacuum, lack of water in the coating mixture, badly beaten plaster
3. When streaking occurs: excess water in the coating mixture.

What is the lost wax process?

Now let's talk about the theoretical part summarized for you to understand. In this type of production, a ceramic wrap is created around a prototype. It is usually made of wax or plastic. The prototype hardens to form the removable casting mold. It is called lost wax because during the process the liquid wax leaks. Moreover, it allows the initial piece to solidify.

Stainless steel lost wax casting process is repeated several times until you have the desired number of wax pieces. They are fixed in a structure that resembles a tree. It interconnects them all in a single entrance hole. This allows the temporary wax pieces to leave and the molten metal to enter.

Ensuite, l'arbre est trempé dans de la céramique et retouché avec du sable. De même, il augmente la résistance et le durcissement de la pièce. Après cela, cet arbre est à nouveau chauffé pour que la pièce ait plus de structure et de rigidité. Cela crée une structure creuse et ne permet aucun choc thermique, ce qui provoquerait la rupture de la structure.

conclusion du moulage à la cire perdue en acier inoxydable

Les transformations des métaux dépendent principalement du moulage à la cire perdue en acier inoxydable . Il est évident que la coulée s'accompagne de plusieurs processus et étapes. Ici, le choix approprié de chaque étape dépend de la géométrie de la pièce, du type d'alliage à couler, du nombre de pièces à produire et de la qualité de surface souhaitée.

Les principaux processus de fonderie sont:

• Moulage au sable;
• Moulage de précision (cire perdue);
• Moulage de moules à gravité permanente;
• Coulée sous pression;
• Coulée centrifuge;